Courtesy Jeff Taylor

Lebanon High School senior Jeff Taylor, 18, with the water gun he uses to play "Assassin," a game that has been banned at New York City's Hunter College High School and others across the country.

An elite New York City high school is warning seniors it could ban them from prom or graduation — or even snitch to college admission officers — if they're caught playing a popular toy-gun game in or near the school building.

The game is called "Assassin" or "Killer," and it's played at schools across the country, usually in May after exams end. Rules vary, but it generally involves students stalking and shooting human targets with water pistols, Nerf darts or plastic disks until only one remains.

Players say it's a fun way to blow off steam, but some school administrators and police officials fear it could turn deadly serious.

"Parents and students should know that we consider this a dangerous game and prohibit playing it on campus," Hunter College High School Principal Tony Fisher wrote in an email to parents last week.

"You should be aware that any students found playing the game within the school or in the immediate vicinity of the building will receive disciplinary consequences."

Fisher declined comment to NBC News but his email details the potential penalties: banning a player from senior events, suspending them, or reporting the incident to colleges if it's not their first serious transgression.

"At least one Senior has been excluded from Prom as a consequence of getting caught playing Killer for each of the last five years,” Fisher wrote.

His concern, echoed by other administrators who have cracked down on the game in recent years, is that the popular diversion is riskier than it seems on the surface.

A student being pursued by an "assassin" could dart into traffic, or a water pistol could be mistaken for a real gun. Teens could be tempted to break laws while they hunt their prey.

Police in Stoughton, Mass., said the dangers aren't purely hypothetical.

"Some of them really do take it too far," said Deputy Chief Robert Devine, recalling a scary incident two years ago.

"It was six in the morning and this kid was proned out [laying on the ground], wearing camouflage, behind a fence, waiting for his target to walk by. A neighbor saw it and the water gun looked like a real firearm and before you knew it, this kid had two officers pointing firearms at him," Devine said.

"And it wasn't the first time we've had calls like that," said Devine, who worked with the local high school to discourage kids from playing the game.

A game in West Jefferson, Pa., was squelched this year after police got reports of teens in high-speed, reckless chases, according to the Pittsburgh Tribune-Review. A Hillsborough, N.J., school was locked down in 2011 after a report of someone pointing a gun out a car window; it was later determined to be a player with a water pistol, the Hillsborough Patch reported.

The NYPD told Hunter that the students' annual "Killer" session overlaps with a gang-initiation period in the city, and that gang members could paint their real guns to look like toys — creating a confusing, dangerous situation for police, Fisher's email said.

At Lebanon High School in New Hampshire, a round of "Senior Assassin" is in its third week after starting with scores of players.

Senior Jeff Taylor, 18, who made it to the semifinals, said he doesn't see anything wrong with it.

"I just have fun doing it," he said. "It's a friendly rivalry and I'm a competitive person."

He said no one could mistake his water weapon for a real gun: "I'm using a super soaker. It's bright orange, blue and green."

Nikayla Cartier, 18, who also attends Lebanon High, said she can "totally understand" why some grown-ups are aghast, "but in all honesty, there's never really been a serious problem."

Cartier, who was eliminated on the first day when someone ambushed her at home, admitted some classmates go overboard. One staked out a spot on a friend's roof like a sniper, waiting for his target to walk by.

"It's extremely stressful because you're watching your back 24-7," she said. "But it’s a good kind of stressful."

Mike Cardew / Akron Beacon Journal Pool via AP

Richard Beasley smiles at his sister Sherri Beasley as he is wheeled into Summit County Common Pleas Judge Lynne S. Callahan's courtroom in Akron, Ohio, on Feb 27, 2013.

Faced with a jury’s recommendation to hand down the death penalty, an Ohio judge will now decide on Thursday, April 4 the fate of the triple killer who lured his victims with Craigslist job offers.

A sentence was expected Tuesday afternoon for 53-year-old Richard Beasley, but Judge Lynn Callahan in Akron said unavoidable complications forced officials to move the sentencing to a later date. 

Beasley, a self-styled street preacher, was convicted last week, found guilty on 26 counts, including nine counts of aggravated murder.

While the jury for the case voted and urged Beasley’s execution, Callahan has the option of reducing the sentence to life in prison. That option could include a chance for parole after 25 or 30 years.

Beasley killed three men and shot another who responded to bogus ads on Craigslist that promised a job as a caretaker on a large farm in Noble County, Ohio. One was killed near Akron and two others were killed at the southeast Ohio farm.

The slain men were Ralph Geiger, 56, of Akron; David Pauley, 51, of Norfolk, Va.; and Timothy Kern, 47, of Massillon. Geiger and Pauley were both buried in shallow graves in a wooded area in Caldwell, Ohio.

The survivor, Scott Davis, testified that he heard the click of a gun as he walked in front of Beasley at the reputed job site. Davis, who was shot in the arm, said he knocked the weapon aside, fled in to the woods and tipped police.

Beasley's teenage co-defendant Brogan Rafferty, who was 16 at the time of the crimes in 2011, was sentenced by the same judge last year to life without parole. Because of his age, he wasn't eligible for the death penalty.

In an opening statement during the sentencing phase of the trial last week, prosecutor Jonathan Baumoel said the "enormous" weight of Beasley's crimes should be considered in deciding on life or death.

Beasley didn't take the stand at the trial's sentencing phase to appeal for mercy. His attorneys instead called a friend of Beasley, a psychologist and his mother, who begged jurors to spare her son's life.  

Beasley had previously served several years in prison on a burglary conviction. 

The Associated Press contributed to this report.

Begging to have jurors spare her son's life, the mother of a triple killer who lured his victims with Craigslist job offers testified Wednesday that he had a troubled childhood and suffered physical and sexual abuse.

"I love Richard with all my heart," a teary-eyed Carol Beasley testified during the sentencing phase of the trial of her son, 53-year-old Richard Beasley. He was convicted last week of killing three men and wounding a fourth, all lured with offers of farmhand jobs in southeast Ohio in 2011.

But despite the emotional plea, the jury on Wednesday evening recommended the death penalty for Beasely. Other options were life in prison without the chance of parole or life with a chance for parole after 25 or 30 years.

Judge Lynne Callahan, who has final say in Beasley's fate, said on Wednesday she will sentence him on March 26.

Beasley's co-defendant, then 16 years old, is too young to face the death penalty. Brogan Rafferty was sentenced to life in prison without the chance of parole on his conviction last year.

In an opening statement at the sentencing part on Wednesday, prosecutor Jonathan Baumoel said the "enormous" weight of Beasley's crimes should be considered in deciding on life or death.

The defense responded by calling witnesses to portray Beasley sympathetically. As his mother testified, Beasley slumped forward, his chin on his chest and his right hand covering his eyes.

She described a difficult childhood for her son, with a verbally and physically abusive stepfather whom Carol Beasley characterized as a mean drunk.

She testified that she learned only within the past year that her son had been sexually abused by neighborhood youngsters when he was a boy. She had known that the boys had forced him to remove his pants in a large drainage pipe but hadn't known about the abuse at the time, she said.

Phil Masturzo / AP file

Carol Beasley, mother of convicted murderer Richard Beasley, leaves the Summit County Courthouse on Tuesday, March 12, 2013, in Akron, Ohio. Richard Beasley was found guilty with aggravated murder in the killing two men from Ohio and one from Norfolk, Va. by luring them with Craigslist job offers.

"I always felt there was much more than he told me," she testified. Her son apparently kept the abuse secret out of fear he would be held responsible for it, the mother said.

Her first husband neglected Richard and her, Carol Beasley testified, and her second husband broke dishes and a window while drinking and whipped Richard as a toddler.

"Richard was very mistreated by him," she testified.

Carol Beasley testified that Richard and the couple's own two daughters would be put to bed early and sometimes were sent to relatives for the weekend to avoid contact with the father.

"Everybody was afraid when he came home," she said.

The defense also called a psychologist, John Fabian, who testified that Beasley suffers from depression, alcohol abuse, low self-esteem and a feeling of isolation, all possible results of a troubled, abusive childhood.

"These are all potential mitigating factors" in favor of leniency, Fabian testified.

Fabian said Beasley's issues should be considered in multi-generational terms involving him and his family life. "This is all his personality development," he said.

One of Beasley's victims was killed near Akron, and the others were shot at a southeast Ohio farm during bogus job interviews.

The slain men were Ralph Geiger, 56, of Akron; David Pauley, 51, of Norfolk, Va.; and Timothy Kern, 47, of Massillon.

The survivor, Scott Davis, testified that he heard the click of a gun as he walked in front of Beasley at the reputed job site. Davis, who was shot in an arm, knocked the weapon aside, fled into the woods and tipped police.

Beasley, who returned to Ohio from Texas in 2004 after serving several years in prison on a burglary conviction, testified that he met with Davis and Davis had pulled a gun in retaliation for Beasley serving as a police informant.

Authorities are looking for the person who fatally shot and beat a pet cat in the lower Hudson River Valley in New York last month, and officials say the suspect may be the same individual who has killed three other cats near the area since July.

Officials in Putnam County say a Patterson, N.Y, man called the local Society for the Prevention of Cruelty to Animals Feb. 7 and said his cat appeared to have been shot while it was outside.

Authorities found the 7-month-old black and brown female Calico cat, named "Blackfoot," with a neck wound; the feline also appeared to be paralyzed from its mid-section to its hind paws.

The cat was rushed to a nearby hospital, where veterinarians conducted an X-ray and found a metal projectile embedded in part of the animal's spine. Animal control officers said the suspect may have used a high-powered BB gun or a low-caliber rifle to fire the projectile at the cat.

Read more news on NBCNewYork.com

Veterinarians also found a spinal fracture that they believe was caused by blunt force trauma.

"I believe the person called her over, the shot her in the back, then kicked her," said Blackfoot's owner Robert Kitts, who found her bleeding outside his home last week.

The cat remained under veterinary care at the Westchester Animal Hospital until it died Feb. 11 due to progressive paralysis, authorities said.

Officials are looking into whether the latest case of cat abuse may be connected to a severed cat head found staged in August in an intersection half a mile from where Blackfoot was shot. Authorities are also investigating if those incidents are connected to two other cat beheadings in July several miles away in the Connecticut towns of Oxford and Fairfield.

"We responded to a call not quite half a mile from here where we found a decapitated cat's head that was placed in the middle of the road," said Ken Ross of the Putnam County SPCA. "That took place within a month of two cats that were found nearby in Connecticut in the same condition."

Authorities are concerned that the cat killer could move to more serious crimes.

"It's moving into the realm of -- something's going to happen to a human," said Ross. "Something's going to be done to a human because this person no longer has the control to hold back."

Anyone with information about animal abuse in the area is asked to call (845) 520-6915 or visit www.spcaputnam.org.

Police on Long Island are resuming their search for a New Jersey sex worker whose disappearance led to the eventual discovery of 10 bodies along a remote barrier beach.   

A police spokesman says investigators will reopen their search for Shannan Gilbert based on new information received Wednesday. He did not say when the search would begin.

Read more coverage at NBCNewYork.com 

Gilbert, then 23, disappeared in the area in May 2010 after apparently meeting a client she had booked through Craigslist. She was seen frantically running from a house in Oak Beach; her body has not been found.

The decision comes as Suffolk County Police Commissioner Richard Dormer revealed that detectives now think that one person is behind the deaths of the human remains found on Gilgo Beach, most of them in the last year.

Most were young women, but one body was a child and another was a man.

"The common denominators that we have now indicate that it's possibly one killer," Dormer said in a phone interview with NBC New York. "We've had the same dumping ground, sex workers, young women -- even though there were the Asian male and the toddler -- but we think they were connected to the sex trade in some way. And these common denominators indicate we have the one person committing these crimes."

He previously said as many as three killers may have been responsible. 

Police also theorize that Gilbert’s disappearance may not be linked to those of the other women.

Dormer declined to detail reasons for the change in theory, but noted all victims appeared connected to the sex trade.

Police said they have received more than 1,200 tips in the case.

This article includes reporting from NBCNewYork.com and msnbc.com staff.

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