Jacksonville Sheriff's Office

Authorities were looking for Rodney Lorenzo Addison, 20, who fled Wednesday, May 15, after a shooting incident at the Jacksonville, Fla., airport.

One person was shot, a second was in custody and at least one other was being sought Wednesday after a Hollywood-style car chase with police bullets flying at the Jacksonville, Fla., airport, authorities said.

The Jacksonville Sheriff's Office said the incident may have been related to a shooting near Highlands Elementary School. It gave no further information, but NBC station WTLV of Jacksonville reported that the lockdown, which was imposed as a precaution, was lifted Wednesday afternoon.

The second shooting occurred in the rental car garage at Jacksonville International Airport about 2:20 p.m. ET, said Jacksonville Sheriff's Chief Tom Hackney, who described a car chase that resembled Hollywood fiction:

Jacksonville SWAT officers following up an auto theft last week spotted the car in question early Wednesday afternoon and began following it as it made its way to the airport, Hackney said at a news conference. Once there, it made its way to the rental car return area, where the driver "stopped in an odd position" that made it clear that he had spotted the trailing officers, Hackney said.

Detectives in two sheriff's cars tried to block the car, one parking in front of it and one behind. The driver of the car, a light-colored Ford Crown Victoria — oddly enough, the vehicle of choice for many of the U.S.'s police forces, among whom it's known as the "Cop Victoria" — began ramming the sheriff's cars, first backing up and then slamming into forward repeatedly, Hackney said.

It worked. The car managed to escape the blockade and sped in reverse through the garage and out onto the street as a sheriff's detective opened fire, striking the car three times, Hackney said.

Other police and sheriff's units that had been alerted to the confrontation began tracking the car, which was found later at a Jacksonville apartment complex. Two men were in the car, a 27-year-old man described as the cars owner and a 17-year-old boy who had been shot in the ankle, Hackey said.

They were arrested, but a third man who was known to have been in the car had fled the scene, Hackney said. A fourth man may also have fled, but that hadn't been confirmed, he said. No law enforcement officers or members of the public were injured, he said.

The man known to be at large was identified as Rodney Lorenzo Addison, 20. He was described only as a black male. Hackney urged residents to take care, saying that while it wasn't known whether Addison was still in the Jacksonville area, "this is a dangerous man — these detectives felt this enough that they used deadly force."

Travelers were allowed back into the airport's rental car area Wednesday afternoon. Aircraft departures and landings weren't affected, the Jacksonville Aviation Authority said.

Follow M. Alex Johnson on Twitter and Facebook.

Watch US News crime videos on NBCNews.com

Carlos Osorio/AP file

The man was flying into Detroit Metro Airport in Romulus, Mich., according to a criminal complaint filed Monday, May 13.

A man traveling with an altered Saudi Arabian passport was in federal court Monday after a pressure cooker was discovered in his luggage at the Detroit airport over the weekend.

The man, identified in a criminal complaint filed in U.S. District Court as Hussain Al Kwawahir, made his initial court appearance Monday on charges of altering a passport and lying to customs officials.

Two pressure cooker bombs were used in the attacks that killed three people and injured more than 250 others last month at the Boston Marathon.

Al Kwawahir, 33, wasn't charged with any terrorism-related offenses, however, and U.S. officials told NBC News they were handling the incident as simply a documents case.

The incident occurred Saturday at Detroit Metro Airport in Romulus, Mich., authorities said. When customs officials noticed that a page had been removed from Al Kwawahir's passport, they examined his luggage and found the pressure cooker, the complaint said.

Al Kwawahir, who was flying into Detroit from Amsterdam, told agents he didn't know how or why the page had been removed.

Al Kwawahir first explained the pressure cooker by saying he'd bought it as a gift for his nephew, who he said was a student at the University of Toledo in Ohio, believing they weren't sold in the U.S. He then changed his story, saying his nephew had managed to buy a pressure cooker in the U.S. but that it had broken.

The complaint didn't explain why the nephew needed someone to fly into the country with a pressure cooker, but the U.S. officials told NBC News that federal agents tracked him down and said he does, indeed, cook with one. 

The Associated Press quoted the young man, Nasser Almarzooq, as saying he'd asked his uncle to bring him the pressure cooker because he wanted to cook lamb and the cookers he bought in the U.S. didn't work.

Watch US News crime videos on NBCNews.com

Pete Williams of NBC News contributed to this report.

Had the Boston explosions happened a few years ago, the buzz would soon be about the color orange. As in “Code Orange” — the government’s way of indicating a high risk of terrorist attacks under the oft-maligned color-coded Department of Homeland Security terror alert system.

Today, the color chart is history, replaced in 2011 by the National Terrorism Advisory System.

So what should travelers know about the state of airport and mass transit security in the wake of the blasts?

No national alerts have been issued, according to the DHS website. In fact, the agency has never issued an alert under the system, which requires the government to send out “formal, detailed alerts” when it receives information about a specific or credible terrorist threat.

The agency did not respond to an on-the-record request for comment about the process, but in a statement issued Tuesday afternoon, Secretary of Homeland Security Janet Napolitano said there is nothing to suggest at this point that the events in Boston are indicative of a broader plot.

“Out of an abundance of caution, DHS continues to keep in place enhanced security measures at transportation hubs, utilizing measures both seen and unseen,” Napolitano said.

She urged the public to remain vigilant and immediately report any signs of suspicious activity. 

“It is notable that they have not used the (NTAS) system to date,” said Christian Beckner, deputy director of the George Washington University Homeland Security Policy Institute.

“The original color coded Homeland Security Advisory System was so broad that it didn’t lead to effective reactions. This more targeted approach is the right one.”

After the deadly Boston blasts, a number of airports are either beefing up police presence or operating under a “heightened state of alert,” including the three major New York-area airports and Los Angeles International. Airlines are extra vigilant, too, and not taking any chances with suspicious items. On Tuesday, a US Airways flight was remotely parked at Boston Logan International “out of an abundance of caution” so that a bag on board could be examined. The baggage was deemed harmless and the flight taxied to the gate. Airport operations were not impacted.

Related: Reports of suspicious activity spur travel headaches

Regardless of whether or not the government issues a national terror alert, TSA can independently send a security notice to the airlines and recommend additional security measures at airports, Beckner told NBC News.

“That’s more precautionary, not necessarily tied to any specific thing,” he said.

The TSA declined to comment about how the Boston explosions are affecting airport checkpoints, referring all questions to the Department of Homeland Security.

If the government issues an alert under NTAS, it will specify whether there is an “imminent threat” or “elevated threat.” The alert will also explain the potential danger, outline what actions are being taken to keep the public safe, and recommend steps that you can take to protect yourself.

“It’s a vast improvement over the last system,” said Rick Nelson, a senior associate of the Homeland Security and Counterterrorism Program at the Center for Strategic and International Studies.

“I don’t think anybody misses the color coded system except for the late night comedians.”

Each threat alert will have an expiration date so the public doesn’t have to deal with an elevated threat level for an unending period of time, Nelson said. That’s quite a contrast from the previous approach, implemented soon after the 9/11 attacks. Road warriors may remember that the threat level in airports remained at orange for years under the color-coded system.

“It wasn’t really based any credible threat and it really didn’t tell people what to do,” Nelson said. “If I told you the threat level was now red, what did that mean to you as a citizen and what should you do differently? That was always very unclear.”

Video of what appears to show a photographer's close call with a stunt airplane is raising safety questions.

The YouTube video shows a stunt airplane owned by Lancaster, Texas-based Viper Airshows nearly slamming into a person with a camera on the runway of the Lancaster Regional Airport south of Dallas. A person on an all-terrain vehicle can be seen riding around in the background.

Also on NBCDFW.com: Man shot 4 times fleeing carjacking

"This was a structured shoot, and some people don't understand that," said the pilot, Jason Newberg.

He said the incident was not an accident.

"All of the people at the practice were briefed and were part of the crew," Newberg said.

Lancaster City Manager Opal Mauldin-Robertson said the pilot has an aerobatic waiver with the Federal Aviation Administration that allows him to perform practice routines for his stunt shows at the airport, provided he does so during the day in good weather, stays within specifically outlined boundaries and follows other safety measures.

"As long as he's in compliance with what's required of him in the FAA waiver, he doesn't need to come in and say, 'I'm going to do a practice run,'" she said Tuesday after viewing the video.

Mauldin-Robertson said she confirmed Tuesday that the pilot's special waiver was still valid and was on file at the airport.

But the FAA said the document shows a November 2012 expiration date on the front.

"Even with a waiver, there a requirement that people on the ground not be endangered," FAA spokesman Lynn Lunsford told NBC 5 by email.

Aviation safety expert Denny Kelly told NBC 5 after watching the video that it was not OK to fly so close to someone on a runway.

"There would be no time that would be the proper thing to do," he said.

The Lancaster city manager said the city had been in contact with the FAA and is awaiting its investigation.

Mark Divita, the airport manager, said told NBC 5 on Tuesday that Newberg had told him that he posted the video on the Internet to drum up attention and promote his upcoming stunt shows.

It was not immediately clear who posted the video, which does not appear on Viper Airshows' YouTube channel.

NBC 5's Ben Russell and Ken Kalthoff contributed to this report.

While not as severe as the two previous days, air travel delays caused by a wintry mix of snow, high winds and heavy rain continued across the country Saturday, while some areas were expecting up to a foot of snow by day's end.

The National Weather Service issued winter storm warnings Saturday for parts of Pennsylvania, West Virginia, New York and Ohio on the East Coast and also parts of Northern California and Oregon on the West Coast.

As of 6 p.m. ET Saturday, more than 6,300 flights had been delayed and 144 were canceled, according to the website FlightStats.com.

Chicago’s O’Hare International Airport and Newark Liberty International Airport in New Jersey were the most impacted, according to the website’s figures.

On Friday, nearly 900 flights were canceled and 13,500 delayed across the country, FlightStats reported.

Weather.com said the storm was likely to linger over northern New England during the weekend.

“Winds will be the most intense from parts of southern New England and New York to the Mid-Atlantic on Saturday,” it said. “Farther to the west, the Great Lakes snowbelts and Appalachians will continue to see wind-whipped snow on Saturday.”

It warned people in those areas to be prepared for winter driving conditions with “sudden reductions in visibility” due to the weather possible.

On Thursday, two people were killed and seven injured in a 30-vehicle pileup on Interstate 35 in Iowa. Drivers were blinded by blowing snow and didn't see vehicles that had slowed or stopped, causing a chain reaction of crashes, state police said.

Thousands of flights disrupted across US as storm hits Northeast

The storm was also blamed for traffic deaths in three other states: two deaths each in Nebraska and Wisconsin; and one in Kansas.

In Utah, a woman who tried to walk for help after her car became stuck in snow died Tuesday night.

The West Coast was also seeing stormy weather.

The NWS said several inches of rain along with several feet of snow in elevated areas were expected in California and Oregon this weekend.

NBC's Ian Johnston contributed reporting.

More content from NBCNews.com:

• Disbelief from some to NRA call for armed guards at schools, blames movies
• NRA chief blames Hollywood, media for violence culture
• Church bells toll 26 times to honor Newtown victims
• Gunman kills woman in church, two others before police kill him
• 48 years later, California couple learns marriage wasn't legal
• Thousands of flights disrupted as storm hits Northeast
• 'Sandy Claus' hands out toys to kids in storm-hit areas
• Escaped robber who rappelled 20 stories is caught
• Video: Scammers prey on Newtown families

Follow US news from NBCNews.com on Twitter and Facebook

The first major wintry storm of the season hammered the Midwest on Thursday, causing a pileup in blizzard conditions that killed three people, dumping a foot of snow in some areas and creating travel problems during one of the busiest periods of the year. Those travel woes could extend into the Northeast, with high winds and rain expected there Friday.

Nearly 600 flights were canceled at Chicago’s O’Hare International Airport on Thursday, according to FlightStats, and an additional 700 were grounded at Kansas City International, Midway (Chicago), Detroit Metropolitan, Minneapolis-St. Paul International and other Midwest airports.

Southwest Airlines canceled all flights at Midway starting at 4:30 p.m. local time, NBCChicago.com reported.

Full coverage of the storm at The Weather Channel

The storm system also spawned a tornado that flipped vehicles in Mobile, Ala., and cut power to 400,000 homes and businesses. Some 130,000 were still without power Thursday afternoon. 

At least six deaths were tied to the snowstorms: In Iowa, three people died Thursday in a pileup involving more than 30 vehicles on Interstate 35, NBC affiliate WHO-TV reported; in Wisconsin, slick road conditions led to two fatalities; and in Utah, a woman who tried to walk for help after her car became stuck in snow was found dead, officials said late Wednesday. Search and rescue crews on snowmobiles found her buried in the snow just a few miles from her car.

Blizzard or winter storm warnings were issued for 16 states on Thursday, Weather Channel meteorologist Mike Seidel told TODAY.

Northeast cities can expect rain and high winds from the system Friday morning, said NBC meteorologist Bill Karins. Most of the snow should move into Canada Friday night.

A foot of snow fell on Des Moines, Iowa, by early Thursday and residents across the state were urged to stay off the roads.

"Because of the wind, travel is pretty treacherous, especially into Iowa, as the storm moves east," National Weather Service meteorologist Scott Dergan said.

The snow cover will drag temperatures much lower in Iowa and Nebraska, he added. "We're talking single digits. We may even see some sub-zero temperatures in Nebraska. This cold weather will stick around for several days, maybe until the day after Christmas. So we're definitely going to have a white Christmas."

Iowa State Police

Some of the vehicles involved in a pileup on Interstate 35 in Iowa are seen Thursday.

Blowing snow led to school closures in parts of Iowa, Kansas, Missouri and Nebraska. All state government offices also closed in Iowa. Storms in those four states left around 130,000 homes without power. 

"Thundersnow" was reported in Iowa Wednesday night, as thunder and lightning accompanied the storm as it trekked across the state. 

Dietra Tate / NBC 15

This vehicle at a car dealership was flipped over by a storm in Mobile, Ala., on Thursday, Dec. 20.

In Alabama, a tornado peeled the roofs off homes and buildings and toppled vehicles in Mobile, but caused no serious injuries, Al.com reported. Arkansas also saw damage from high winds.

The storm system earlier delivered heavy snow and strong winds to parts of the West, where trucks tangled on icy roads on the Oregon and California state line.

Snowstorm prompts state of emergency in Wisconsin

In West Texas, winds from the same system kicked up a dust storm Wednesday that caused accidents along Interstate 27, resulting in one death and more than a dozen injuries, NBC affiliate KCBD reported.

At Dallas-Fort Worth airport, American Airlines said it canceled about 120 flights Wednesday night due to the storm. 

In Nebraska, snow blowing sideways on Wednesday night forced the closure of a 146-mile stretch of Interstate 80, a major east-west highway. 

In Wisconsin, Gov. Scott Walker declared a state of emergency on Wednesday. Schools were canceled in advance of heavy snowfall and the University of Wisconsin-Madison postponed Thursday’s final exams.

Before the storm, several Midwest cities had broken records for the number of consecutive days without measurable snow.

In Chicago, people made a run on snow shovels and salt ahead of what should be the first snow to hit the city in 290 days (the record is 296). 

The storm has package delivery companies nervously checking the weather forecast during this busy time of year. "We’re closely monitoring the storm," FedEx spokesman Scott Fiedler told NBC News. "We have a team of 15 meteorologists who track the weather around the world every day."

Related: UPS, FedEx weather experts work on timely deliveries
Related: Chicago braces for 'thundersnow'
Related: Bad in US? Try Russia, where some parts as low as 50 below
Related: Slideshow of wintry scenes around the world

Along the East Coast, the I-95 corridor isn't expected to see much, if any, snow.

"Snow may make it as close to New York City as Western Connecticut but right now, other than a few flurries Friday night, I think New York City through Boston will be mostly snow-free," Tom Niziol, the winter weather expert at The Weather Channel, told NBC News.

"Areas to the southeast of the Great Lakes, from Cleveland through Syracuse will get heavier snowfall," he added. "Higher elevations from the Adirondacks through the western slopes of the Central Appalachians will also get snow."

NBC News' Isolde Raftery and A. Pawlowski, as well as The Associated Press and Reuters, contributed to this report.

More content from NBCNews.com:

• Cardinal: Teacher who gave her life is 'like Jesus'
• Holiday travel alert: Storms deliver foot of snow in central US, tornado in Alabama
• 'You feel helpless': First responders rushed to school after shooting, only to wait
• Mayan end-of-world rumors prompt Michigan officials to close 33 schools
• Reported sex assaults leap 23 percent at US military academies
• Video: Should school kids carry bulletproof backpacks?

Follow US news from NBCNews.com on Twitter and Facebook