LEWISTON — A 15-year-old high school student suspended for taking a squirt gun to school likely was playing a game known nationally as “Assassin,” according to police, school officials and parents of other teens.

One parent described it as a harmless game with written rules that stress that it is not to be played on school grounds. Police and others, however, are wary about a pastime that involves fake guns and a goal of eliminating opponents.

Call it zero tolerance with a twist.

One father said his son has been ordered, by school and police officials, to put a halt to the game, even though it is typically played away from school.

“This game has been going on at (Lewiston High School) for years,” the parent said. “I have had two kids go through LHS and they played it every year. This is an innocent game that is a lot of fun for the kids that really has nothing to do with LHS, but because my son is a kid who goes there, and they are in a position of authority, they pretty much bullied him to stop it.”

Police see it a different way.

In the past few weeks, Lewiston police have gotten calls from people who see teens behaving in ways that make them nervous, said Detective Sgt. Joe Bradeen, who is in charge of youth and family services.

“They’ve seen strange vehicles parked in their neighborhoods, or persons on foot traveling through neighborhoods they don’t recognize,” Bradeen said Thursday. “It’s good folks are calling us; they’re on alert.”

He said some squirt guns can look like regular firearms. “That can be an issue, seeing someone with a gun that looks real tucked in their waistband, running through a neighborhood or hiding in a bush. It’s a safety issue.”

Another safety issue is that homeowners who see kids playing the game might shoot at them, Bradeen said.

“And we’re talking about kids doing this at 5 or 5:30 in the morning,” he said. “They go out to get (their assigned target) early, before they leave the house. Or they’ll play late at night.”

The 15-year-old suspended this week was disciplined after a bright yellow squirt gun allegedly fell out of his backpack. The teen has neither confirmed nor denied involvement in the game of Assassin.

While playing the game with squirt guns “may seem like a lot of fun, it should only be played in backyards, not on school grounds,” said Bill Webster, superintendent of Lewiston schools. “We already know there are students who are focusing on the game, and not on their studies.”

The game has been in existence for years. Online, Wikipedia has a page detailing the facets of the game. WikiHow features directions on how to form a group and to institute rules of play. The New York Times published a long expose of Assassin in 2008.

Around the country, high schools and some colleges are cracking down on the game after a few high-profile incidents involving players. Webster referred to a recent situation in Manchester, N.H., in which cars crashed as students were stalking each other as part of the game.

The game can be disruptive in a school setting, Webster said.

“I find it interesting that students are not able to look at the big picture and see what this game means,” he said.

Some people reacted with shock and disgust that a squirt gun could warrant a student suspension. Webster disagreed, saying anything that could be construed as a weapon should be left at home.

“It’s something not to be brought to school,” he said. “School is for academic learning. We’re not in the business of drawing a fine line on one squirt gun that is acceptable and one that isn’t.”