Suburban police warn of consequences with popular ‘Senior Assassins' game

Police are warning about potential consequences for teens playing a popular game known as "Senior Assassins," if they don't play it properly.

Authorities in several Chicago suburbs have put out alerts about the nationwide game, which is set to soon be played in multiple locations.

But what is it, how is it played and why might it be dangerous?

Here's what to know:

What is "Senior Assassins" and how is it played?

According to police, the game involves forming teams for a "tournament-style competition" in which students eliminate competitors by "tagging" them with water guns. The rules of the game, however, vary by location.

In Arlington Heights, police said the "live action game" is an "annual springtime tradition for students," particularly seniors.

"Game rules specify the activity cannot take place during school hours or on school property. Players attempt to locate their opponents at various sites including home, local parks, and other gathering spaces within the community," police said. "Students will often hide in odd spots, chase targets through yards and appear suddenly in a vehicle or on foot."

In Bartlett, authorities said rules of the game prohibit trespassing "or any other illegal activities."

In Gurnee, for example, officials said "it's common for players to wear ski masks to catch their opponents off guard."

Why are officials warning about the game?

Police in several suburbs, including Gurnee, Bartlett and Arlington Heights, put out community alerts surrounding the game, some noting "concerning incidents" associated with it.

In Gurnee, a group of high school students from another suburb entered a restaurant wearing ski masks and holding water guns that police said resembled firearms.

"They were targeting other students who were dining in the restaurant and attempting to spray them with water," police said in an alert. "An adult, who was a concealed carry holder, in the restaurant mistook the situation for a genuine threat, and the situation could have escalated quickly. The gravity of the situation cannot be emphasized enough; it had the potential to lead to serious consequences."

Officials noted that others in the restaurant were left frightened by the scene and the students were given a warning.

"Two guys came in with hoodies on ski masks and what appeared to be real weapons, so you can imagine the fear… they had no idea what was going on, was it a robbery, was it someone creating an active shooter incident, we don’t know," Det. Shawn Gaylor with the Gurnee Police Department told NBC Chicago.

"If you are going to be using ski masks, weapons that look like real firearms, that’s a cause for concern. And that’s where you have to think about the effects on everyone else," Gaylor added.

In Bartlett, village officials warned the game begins on April 14. There, authorities said rules of the game prohibit trespassing "or any other illegal activities." There, authorities noted that officers in nearby towns, including St. Charles, have responded to 911 calls made by residents concerned about people wearing masks or hoodies lurking around homes or suspicious vehicles driving around neighborhoods.

"Some of these reports also involved participants driving on lawns or brandishing water guns that looked like realistic-looking handguns (as shown in the pictures), which has caused concern for the responding officers since they were unable to tell whether the participating students were committing actual crimes or simply playing a game," the alert said.

Are there potential consequences?

In each case, police said they do not condone the game and some expressed concerns with school officials.

"The concept is not against the law or a local ordinance. We ask everyone to play safely, use common sense and recognize how players’ actions may be perceived by members of the community," Arlington Heights police wrote in their alert. "The unintentional result of participants running throughout the community with a water gun, some often resembling a look-alike firearm, could have deadly consequences."

Gurnee warned that some cases, particularly those that take place in public spaces, could result in disorderly conduct charges, "as they often cause feelings of being alarmed and disturbed by others."

Bartlett officials encouraged parents to talk to their children about the game "to ensure they are aware of the potential issues that could arise from participating."

"There are a lot of people out there who are on edge, who have cc permits, and may perceive it entirely different for our community," said Barlett Police Chief Geoffrey Pretkelis. "We are just asking parents and students to be respectful, and to be careful."