GREENSBURG, Pa. – Hempfield Area Senior High School officials are warning parents about a “serious safety issue” involving area teens: a game called “Squirt Gun Assassin.”

Principal Kathy Charlton sent a letter to parents recently warning them of the dangers of the game “Squirt Gun Assassin” in which students assassinate each other with squirt guns, a tradition with seniors she said is getting out of control, KDKA reports.

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“There have been incidences of teens chasing each other in cars, teens chasing school buses, and teens stalking each other in public places such as mall restaurants and at private homes,” the letter warned.

The letter states police have been called about the game several times.

Freshman John Malinac told the news site only seniors are involved, and the winner gets a cash prize.

“They basically assign a senior to squirt gun fire at other seniors, and once they hit that person, then they’re out and they get assigned another person,” Malinac said.

“It’s all in fun and games,” the boy’s father, Mike, told KDKA. “As far as I’ve known no one has ever gotten hurt doing it, but sometimes things get out of hand.”

Other parents also don’t seem very concerned about the “dangerous” squirt gun game.

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“It was my understanding that when this all started, there is a bunch of rules to follow,” parent Wendy Eperesi said. “You can’t go into somebody’s house, things like that.”

Charlton clarified in her letter that the school does not condone the game, and prohibits students from playing on school property, the Associated Press reports.

Several Hempfield seniors weighed in on the controversy in conversations with WPXI.

“I think squirt assassin is a good way for our school to come together,” Gabriella Lonzo said. “Some people take it too far and ruin it.”

“It’s kind of fun,” Cameron Repasky said, “but people get way too serious about it and they never want to admit they’re out.”

The news site reports the winnings for this year’s Squirt Gun Assassins is $800, and Charlton said competition for the cash is fierce.

“The kids organize brackets and they try to squirt each other and the last person standing who wasn’t squirted wins the pot of money,” she said. “We’re pretty much down to the last few kids now, so it’s become very aggressive.”

School officials told WPXI students caught playing the game at school will face discipline.

Students also use the game to raise money for charity and have donated hundreds of dollars to important causes, they told the news site.