Michelle McLoughlin/Reuters file

Mark and Jackie Barden, parents of Daniel Barden, 6, a victim of the shootings at Sandy Hook Elementary School, holding a picture of their son on Jan. 14. They spoke out against the compromise legislation Monday, April 1, in Hartford, Conn.

Lawmakers and families of the victims of the deadly shootings last year at a Connecticut elementary school were divided Monday over compromise legislation that would ban some but not all high-capacity ammunition magazines in the state.

Lawmakers announced Monday afternoon that they had reached a deal on a bipartisan measure designed to limit high-powered weapons, 3½ months after 20 children and six other people were killed at Sandy Hook Elementary School in Newtown.

Related: Connecticut lawmakers reach deal on 'most comprehensive' gun limits in US

The Legislature will convene Wednesday, with a vote expected as early as this week.

The would ban the sale of magazines able to handle more than 10 bullets. Adam Lanza, the gunman in the Dec. 14 shootings, used magazines accommodating 30 bullets.

But in a compromise, the lawmakers included a "grandfather clause" allowing people who already own such magazines to keep them, subject to registration.

Families of the Newtown victims objected, sending a letter to legislative leaders Monday saying more children might have survived had Lanza been carrying smaller magazines.

Lanza "fired 154 shots in approximately 4 minutes, killing 20 children and 6 educators. Miraculously, in the time that it took him to reload in one of the classrooms, 11 children were able to escape and are alive today," they said in the letter, which is reprinted below.

"We are left to wonder, what if the Sandy Hook shooter had been forced to reload not 6 times but 15 times. Would more children, would our children, be alive today?"

Mark Barden, whose son Daniel died in the shootings, said at a news conference Monday in Hartford: "The more times you have to reload, the more opportunities there are to escape and to stop the shooting. In the amount of time — it was somewhere around four minutes — he was able to fire 154 rounds. I think that speaks volumes about reducing the size" of magazines.

Connecticut Gov. Dannel Malloy sided with the parents.

"I have been clear for weeks that a ban on the possession and sale of high capacity magazines is an important part of our effort to prevent gun violence — simply banning their sale moving forward would not be an effective solution," Malloy said in a statement Monday. 

"This morning, we heard from victims' families on that very point. They've asked for an up or down vote on that provision and, whether it's in the larger bill or as an amendment, the families, and every resident of our state, deserve a vote."

Following is the letter parents of the Sandy Hook victims sent Monday to Connecticut legislative leaders:

Dear Senators and State Representatives,

We, the parents of children killed at Sandy Hook Elementary School together with the parents and spouses of educators killed that day in Newtown, are writing today regarding gun legislation currently under consideration by Connecticut's legislature. We are grateful for your leadership on this issue and for the efforts of the Bipartisan Task Force on Gun Violence Prevention and Children's Safety to craft a comprehensive package of legislation to keep our communities and children safer from violence. We feel strongly, however, that the current proposed action on large capacity ammunition magazines is inadequate and must be strengthened.

We feel a very personal connection to this issue. The Sandy Hook shooter carried 10 magazines that held 30 bullets each. We now know that he left many smaller magazines at home. He fired 154 shots in approximately 4 minutes, killing 20 children and 6 educators. Miraculously, in the time that it took him to reload in one of the classrooms, 11 children were able to escape and are alive today.

We are left to wonder, what if the Sandy Hook shooter had been forced to reload not 6 times but 15 times. Would more children, would our children, be alive today?

The current proposal under consideration in Hartford would allow the sale of magazines with a capacity of 10 bullets or fewer. The proposal, however, grandfathers existing large capacity magazines leaving a gaping loophole on, what we believe, is the most dangerous feature of an assault weapon. Individuals will easily be able to purchase high capacity magazines in other states, bring them to Connecticut and claim to have owned them before the law took effect. Proving that the purchase or transfer took place post-enactment will be difficult, if not impossible.

Additionally, the "grandfathered" possession of large capacity magazines is not in the public interest and exposes our communities to an unacceptable risk of additional mass shootings. We must do more. If there is reason to stop the further sale of magazines that hold more than 10 bullets, a principle with which we wholeheartedly agree, it makes sense to take steps to prevent the potential damage that existing magazines could cause. How can we not remove large capacity magazines from Connecticut if we know that it might save even one more child or teacher or parent?

On behalf of the loved ones who were violently taken from us, please reconsider your approach to large capacity magazines as part of the comprehensive package of gun legislation. We are calling today for an up or down vote on the issue. Thank you for your consideration of our views.

Follow M. Alex Johnson on Twitter and Facebook.

This story was originally published on Mon Apr 1, 2013 8:17 PM EDT

Jessica Hill / AP file

David Wheeler, father of Sandy Hook School shooting victim Benjamin, listens to a legislative hearing of a task force on gun violence and children's safety at Newtown High School in Newtown, Conn., on Jan. 30, 2013.

Connecticut lawmakers on Monday said they had reached an agreement on compromise gun control legislation that they said would be one of the toughest in the nation, 3½ months after 20 children and six other people were killed in a mass shooting at an elementary school.

The bill includes a ban on large-capacity ammunition magazines like those Adam Lanza used to fire 154 shots in four 4 minutes Dec. 14 at Sandy Hook Elementary School in Newtown, a new registry for existing high-capacity magazines and background checks for private gun sales, NBC Connecticut reported.

While the measure would ban the sale of ammunition magazines able to handle more than 10 bullets, Gov. Dannell Malloy and parents of the Sandy Hook victims objected to a "grandfather clause" that will allow current owners of such magazines to keep them.

But state Rep. Gary Holder-Winfield, a Democrat representing New Haven, told NBC Connecticut that the bill, which could be voted on as early as Wednesday, would still impose some of the nation's toughest gun control laws on Connecticut residents.

At a news conference Monday, Senate Minority Leader John McKinney, a Republican whose district includes Newtown, agreed that the deal was "the most comprehensive package in the country because of its breadth," The Associated Press reported.

In what was being described as a first in the U.S., gun owners would have to register current magazines accommodating more than 10 rounds with the state by January, The New Haven Register reported.

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The measure would also require universal background checks for all firearm sales — many states don't require them for private sales, such as those between family members or collectors — and would add 34 more weapons to the state's list of banned semi-automatic assault-style weapons. 

The Register reported that the bill would also strengthen penalties for gun trafficking and would expand the Board of Firearms Permit Examiners to include a mental health professional and a retired judge.

House Speaker Brendan Sharkey, a Democrat representing Hamden, told reporters the measure was meant to send a message to Washington that "this is the way to get this job done."

Follow M. Alex Johnson on Twitter and Facebook.

Related: 'Grandfather clause' in Connecticut gun bill angers Sandy Hook families

Adam Lanza left a home stuffed with weaponry and carried out the massacre at Sandy Hook Elementary School in a 154-bullet barrage that took less than five minutes, investigators said Thursday in the first detailed account of his surroundings and troubled state of mind.

Search warrants from the second-worst school shooting in American history revealed that the home Lanza shared with his mother in Newtown, Conn., was a veritable arsenal: Authorities found at least nine knives, three Samurai swords, two rifles, 1,600 rounds of ammunition and a 7-foot, wood-handled pole with a blade on one side and a spear on the other.

Authorities also recovered a certificate in Lanza’s name from the National Rifle Association, seven of his journals, drawings that he made and books from the house, including books on living with mental illness.

The warrants offered a thorough look at the environment in which Lanza lived before he shot his mother, Nancy, to death and drove to Sandy Hook on the morning of Dec. 14. Twenty first-graders and six teachers and staff were killed before Lanza shot himself to death with the 155th bullet.

An FBI report based on interviews with people who knew him said that Lanza rarely left home, considered himself a shut-in and was an avid gamer who played “Call of Duty,” a first-person shooter game. Lanza considered the elementary school his “life,” the papers said.

Among other items seized from the home were a holiday card containing a check from his mother to buy a firearm, an article from The New York Times about a 2008 school shooting at Northern Illinois University and three photographs of what appeared to be a dead person covered with plastic and blood.

List of Lanza's arsenal, item by item

Read the warrants, search them

The books included “Look Me in the Eye: My Life with Asperger’s” and “Born on a Blue Day: Inside the Mind of an Autistic Savant.”

At the school, Lanza fired the 154 rounds from a Bushmaster .223-model rifle and the final bullet from a Glock 10mm handgun to take his own life, said Stephen Sedensky, the chief prosecutor investigating the shooting. Police recovered 10 30-round magazines for the Bushmaster that Lanza took to the school. Three of the magazines had a full 30 rounds still in them.

Among school shootings in the United States, the death toll from Newtown is second only to the 32 people killed at Virginia Tech in 2007.

The attack touched off a nationwide debate about gun control. The fate of proposed changes to national gun laws, including expanded background checks and limits on high-capacity magazines, remains unclear.

President Barack Obama spoke Thursday at the White House to make the case again for tougher gun laws. He appeared with parents of Sandy Hook victims and of other gun crimes but did not specifically reference the newly released Newtown warrants.

“The entire country was shocked,” the president said. “And the entire country pledged that we would do something about it and this time would be different. Shame on us if we’ve forgotten. I haven’t forgotten those kids. Shame on us if we’ve forgotten.”

Connecticut Gov. Dannel Malloy, citing the warrants, also called for stricter gun laws.

“We knew that these weapons were legally purchased under our current laws,” Malloy said. “I don’t know what more we can need to know before we take decisive action to prevent gun violence. The time to act is now.”

The warrants spelled out a vast inventory of weapons and other gun paraphernalia recovered from the Lanza home.

Among the items found were paper targets, gun manuals, earplugs, holsters, almost 40 types of ammunition, nine types of magazines, a bayonet, knives with blades as long as a foot and Samurai swords with blades as long as 2 feet 4 inches.

Authorities also found a starter’s pistol, a BB gun, an NRA guide to pistol shooting and an NRA certificate in Nancy Lanza’s name.

In a statement, the NRA said it had no record of a “member relationship” for the Lanzas, nor for someone with the same last name and their first initials.

“Reporting to the contrary is reckless, false and defamatory,” the statement said.

On Wednesday, a judge granted a request from prosecutors to withhold some information in the records, including a witness name, credit card information, telephone numbers and serial numbers.

Besides the Bushmaster and the Glock, authorities found a Sig-Sauer 9mm semiautomatic pistol in the school. In the car outside, police found a shotgun.

All those weapons were legally owned by the mother, authorities have said. Enough public blame and anger has been directed at her that she was left out of many of the memorials and shrines to the Newtown victims.

There have been reports that Lanza was obsessed with other mass killers, including Anders Breivik, who killed 77 people in a shooting and bomb attack in Norway two years ago.

A law enforcement official told NBC News last month that Lanza had collected material on previous mass shootings, although the source said there was no indication that it played a role in the school massacre.

Police told NBC News in February that investigators were still a long way from determining Lanza’s motive. Police said then that they hoped to have a report on the shooting finished by June.

Search warrants:

Dec. 14 (first) | Dec. 14 (second) | Dec. 14 (third) | Dec. 15 | Dec. 16

This story was originally published on Thu Mar 28, 2013 9:23 AM EDT

Lucas Jackson / Reuters file

Nancy Lanza's home in Newtown, Conn., on Dec. 18.

Search warrant documents in the Sandy Hook massacre are expected to be released early Thursday and could shed more light on gunman Adam Lanza’s state of mind and motive in carrying out the second-deadliest school shooting in U.S. history.

The records were sealed in the immediate aftermath of Lanza’s Dec. 14 shooting rampage through the Newtown, Conn., elementary school, and Connecticut Superior Court Judge John F. Blawie extended the order for 90 days on Dec. 27 (here in .pdf). It covered the applications, affidavits and returns for five search warrants for the home in Sandy Hook where Lanza lived with his mother, Nancy, and for the black 2010 four-door Honda Civic sedan that he parked in front of Sandy Hook Elementary School.

Rhonda Stearley-Hebert, communications manager for the Connecticut Judicial Branch, said Wednesday that the documents would be available Thursday morning. A statement from prosecutors working on the case also was expected to be made public.

On Wednesday afternoon, Blawie granted a motion from the state's attorney to redact some information in the records, including a witness name, a credit card number, telephone numbers and several paragraphs of one item. Serial numbers for several unidentified items also will be redacted. The sealing orders will be lifted at midnight Wednesday, and the documents were to be released by email at 9:01 a.m. Thursday.

Authorities say Lanza shot his 52-year-old mother to death at the home they shared on the morning of Dec. 14, then drove about five miles to the school, where he killed 20 first-graders and six teachers and staff members before fatally shooting himself. Two other teachers were wounded. The death toll is second only to the 32 killed in the 2007 Virginia Tech massacre among U.S. school shootings.

Lanza, 20, used a Bushmaster .223-caliber XM15-E2S rifle with a 30-round magazine to shoot the victims at the school, authorities have said. In addition to the Bushmaster, authorities found a Glock 10mm semiautomatic pistol and a Sig-Sauer 9mm semiautomatic pistol in the school – one of which Lanza used to kill himself. In the Civic parked outside, police found an Izhmash Canta-12 12-gauge shotgun, which looks similar to a Kalashnikov rifle; it was not used at the school.

All those weapons were legally owned by Nancy Lanza, authorities have said. There have been reports that several more guns were found in her home, though NBC News has not confirmed that.

On Wednesday, the Lanza home looked untouched since the shooting -- a large Christmas wreath still at the door and holly wrapped in perfect form around the columns.

Authorities have kept tight control over information in the case, including any evidence that might give clues to Adam Lanza’s motivation.

There have been reports that he was obsessed with mass killers, including Norway’s Anders Breivik, who killed 77 people in a shooting and bomb attack in 2011. A law enforcement official told NBC News last month that Lanza had collected material on previous mass shootings, although the source said there was no indication that it played a role in the school massacre. Some reports also have suggested that investigators believe violent video games might have helped propel Lanza to violence, though authorities have not confirmed that. Like many young adults, Lanza was known to play a variety of video games, some violent and some not.

Connecticut State Police spokesman Lt. Paul Vance told NBC’S TODAY in February that investigators “are a long way” from determining Lanza’s motive. Vance said investigators hope to have their report on the shooting completed by early June.

Access to information has become an issue with state lawmakers working on bipartisan gun-control legislation stemming from the massacre.

Lawmakers complained last week after the New York Daily News reported that a state police commander had disclosed evidence about the case at a law enforcement seminar in New Orleans. State House Republican Rep. Larry Cafero said lawmakers should be getting more information for their deliberations, and in response, Gov. Dannel P. Malloy said the Office of the Chief State’s Attorney had agreed to release more information this week.

Mark Dupuis, spokesman for the state Division of Criminal Justice, said Wednesday that the release would include the search warrant documents and a statement from prosecutors.

Adam Joseph, communications director for the state Senate Democrats, told NBC News on Wednesday morning that lawmakers still did not have a final agreement on the legislation and were waiting to see the search warrants before scheduling a vote, which could come as early as next week.

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Carlo Allegri / Reuters

People walk past a makeshift memorial in Sandy Hook after the Dec. 14, 2012 shooting tragedy , in Newtown, Connecticut, on Dec. 28, 2012.

Students from Sandy Hook Elementary School will go back to class Thursday in a borrowed building that one police official described as “the safest school in America.”

They will enter classrooms that have been furnished to look like the ones they left last month, as Adam Lanza carried out his massacre.

Desks and even abandoned backpacks and coats have been brought from Sandy Hook in Newtown, Conn., to the new school in Monroe, seven miles away.

Greeting the youngsters will be Donna Page, who was the principal of Sandy Hook until she retired in 2010. She agreed to come back after her successor, Dawn Hochsprung, was killed in the rampage.

Pupils and parents had a chance to tour the new building – an unused former middle school – on Wednesday after Connecticut Gov. Dannel Malloy met with teachers.

When they return at 9 a.m. Thursday, they will find counselors and extra police on hand.

“It feels extremely secure there,” Newtown School Superintendent Janet Robinson told reporters.

Police declined to say what security measures were in place, but Monroe Lt. Keith White said parents don’t have to worry.

“Right now, it has to be the safest school in America,” he said.

David Connors, 40, who has 8-year-old triplets, said he knows that sending his kids back to school will be difficult – but crucial.

“The past three weeks have been just crazy,” he told NBC Connecticut.  “Getting back to that sense of figuring out what the new normal is going to look like, I think, is important. Everyone is waiting for that to happen.”

His children, he said, are ready for the transition.

“They want to see their teacher. They want to see their classes. They want to get back into a routine,” he said.

The 500 students have not been in school since Lanza blasted his way into Sandy Hook on Dec. 14 and killed 20 children, six staffers and himself. He had earlier killed his mother.

Teachers from Newtown and Monroe spent their holiday break readying the new building for the children, and Robinson said it looks “cheerful and happy” and is decorated with paper snowflakes sent in from around the world.

She said the first day back will be as ordinary as possible, and the school will wait some time to honor teachers for their bravery during Lanza’s killing spree, which was largely confined to two first-grade classrooms.

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"There's certainly going to be children that are scared,” Thalia Andernen, a counselor with The Center of Hope, a nonprofit family support center, told NBC New York.

“They're going to be frightened and feel very insecure about going back, but a lot of them are going to be resilient.”

With no decision on what will happen to the Newtown building, the former middle school in Monroe has been renamed Sandy Hook Elementary, and the sign has been removed from the old school.

After so many funerals, there are signs of Newtown’s slow recovery. The large memorials that overtook the town have vanished and the Fire Department’s flag is back at full mast, although the station roof still bears a reminder of the toll: 26 stars.

In Monroe, officers were stopping cars that tried to stop near the new school and asking them to move on. Down the road, someone from the town had hung a sign for the Sandy Hook kids who will be coming there for the foreseeable future: "We Are So Proud Of You.”

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Updated at 7:34 p.m. ET: Adam Lanza, who authorities say killed 20 children and six women in Connecticut, shot his mother in the head multiple times before heading to Sandy Hook Elementary School, where he fired hundreds of rounds and died with hundreds more at his disposal, police said Sunday.

It was an extraordinary amount of weaponry that Connecticut State Police Lt. Paul Vance described Sunday. In addition to an assault-style rifle and at least two handguns, he also had a shotgun in reserve in the car he drove to the school.

And when he was found, Lanza, 20, still had "hundreds of rounds" of ammunition in multiple magazines, after having already fired hundreds of rounds inside the school, where he killed himself with a gunshot to the head as emergency crews arrived Friday. 

An explanation still hasn't emerged for why Lanza killed the 26 people at Sandy Hook, but Connecticut Gov. Dan Malloy opened a window for speculation when he told NBC News on Sunday that it appeared that Lanza attended the school as a youngster. Earlier reports that his mother, Nancy, may have taught there haven't borne out. 

"He attended there — that's what I'm led to believe," Malloy said on NBC's "Meet the Press."

The children — 12 girls and eight boys, all of them 6 or 7 years old — were shot as many as 11 times, H. Wayne Carver, the state medical examiner, said Saturday. It appeared that Lanza had enough weapons and ammunition with him to have killed many, many more.

Police were analyzing the weaponry, along with a computer they found at the Lanzas' home, for possible leads on the gunman's motive, NBC News' Pete Williams reported.

Conn. shooting suspect Adam Lanza's father: 'We too are asking why'

Lanza's parents were divorced, and he lived with his mother, who home-schooled him for part of his childhood, Malloy said.

Connecticut school shooter was 'very nervous around people'

 "He had a very troubled life," Malloy said. "He never seemed to be a good fit. ... It was a very difficult time for him and his mother."

Malloy declined to answer whether any documented evidence had been uncovered that Lanza might have been mentally disturbed. At Western Connecticut State University in Danbury, where he enrolled at about 16 in 2008, there was never any indication of trouble, the university said in a statement Sunday.

Lanza took six classes — including website production, data modeling, Philosophy 101 and ethical theory — and compiled a solid 3.26 grade-point average.  

Investigators resolutely refused to go into detail about the timing of events Friday during official briefings. But investigators told NBC News that Lanza first killed his mother, an avid gun enthusiast, with her own gun and then took multiple weapons with him as he drove to the school in her car.

To bypass security, Lanza smashed in a window, they said. He shot and killed Principal Dawn Hochsprung, 47, and Mary Sherlach, 56, a school psychologist, before proceeding to a classroom, where he found the door locked.

So he moved on to a second classroom, where he killed everyone he found, before doing the same in a third classroom, investigators believe. He then shot himself.

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Although he was carrying three weapons, he used only one of them in all of the school killings — a Bushmaster .223-caliber assault-style rifle similar to the one used by the snipers who terrorized the Washington, D.C., area in 2002. It was purchased legally, they said. He used one of the handguns to kill himself.

Authorities haven't said how Nancy Lanza stored the weapons. 

Marsha Lanza, Nancy Lanza's sister-in-law and Adam Lanza's aunt, said there was a good reason for a divorced woman who grew up with guns to have them in the house: self-defense.

"She lived alone. She was a female (who) lived alone," Marsha Lanza said.

Chief Justice Correspondent Pete Williams and Isolde Raftery of NBC News contributed to this report.

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