In some cases, the water guns are being mistaken for real weapons, triggering emergency responses at local high schools.
High school students are being spotted with water guns and swim goggles on their heads -- many of them are playing a tag-like game called "Senior Assassin," as part of a social media trend.
The objective is not to get eliminated, and while it may seem like harmless fun, it has sparked safety concerns.
"The problem is these kids are using water guns that look like real guns," said Nassau County Police Commissioner Patrick Ryder.
Ryder told Eyewitness News that police recently responded to two separate reports of a potential active shooter or person with a gun at high schools, prompting school lockouts. In both instances, the "weapons" were water guns.
Ryder said a 911 call about the viral trend this week prompted a lockout at Plainedge High School.
"If we have a person with a gun at a school, and we got a legit 911 call coming in like this one was, we're coming, BSO, POP officers, we're all coming," Ryder said.
Police have sent flyers to area high schools and are urging parents to speak with their children about the potential dangers of the game.
Officials say it can lead to confusion, fear and hazardous situations.
"I hate to say this, but its not acceptable, you cant have kid running around with guns that look like guns," Ryder said.
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