What high school students see as a harmless end-of-year tradition is drawing urgent warnings from law enforcement nationwide.
The viral “Senior Assassin” water gun game has increasingly spilled into the public eye, triggering panicked 911 calls from bystanders and forcing responding officers to make split-second decisions.
The decades-old game is typically played by graduating seniors who are assigned classmates as “targets.” Players attempt to “eliminate” one another using water guns, often recording the encounters for social media. Rules vary by school or group, but many versions involve entry fees, cash prizes, video proof and rounds of elimination until one winner remains.
While many students see the game as a harmless end-of-year tradition, police say the circumstances surrounding it — students hiding near homes, wearing dark clothing or masks, carrying realistic-looking water guns and approaching schools or businesses — can quickly trigger 911 calls and armed police responses.
What is ‘Senior Assassin’?
“Senior Assassin” is essentially a water gun version of tag, usually played by high school seniors in the weeks leading up to graduation. Students are assigned a target and attempt to spray that person with a water gun before being eliminated themselves.
The game is not new. Many online commenters trace the broader “assassin” game concept to Steve Jackson Games’ Killer: The Game of Assassination, an early live-action role-playing game in which players “stalk” targets using harmless stand-ins for weapons, including squirt guns and water balloons.
But social media has changed how the game is played and seen. On TikTok, students often document their “Senior Assassin” runs through storytime videos, elimination clips and updates on who remains in the game. Some videos show players following classmates into public places, including stores and parking lots, which can create confusion for people who are not aware a game is being played. Some versions require players to record their eliminations as proof, adding another layer of public visibility to what was once a more localized senior prank.
Why police are warning students and parents
Law enforcement agencies are not warning about the game simply because students are carrying water guns. Their concern is what the game looks like to everyone else.
In Stoneham, Massachusetts, police said a 911 caller reported a person hiding in a bush near a home while holding what appeared to be a firearm. Officers arrived within two minutes on May 4 and detained a teenager, later determining he was playing “Senior Assassin” with a realistic-looking water pistol. Chief James O’Connor said the incident was resolved safely because the teenager was compliant and officers remained calm, but he called it a “potentially dangerous misunderstanding.”
Similar concerns have been reported elsewhere. The Union County Sheriff’s Office in North Carolina said deputies responded to calls involving teens wearing dark clothing and masks while carrying water guns that closely resembled real firearms. The agency urged parents to talk with teens about the risks of hiding around homes, chasing people, driving erratically or carrying items that look like weapons.
In New Brunswick, the RCMP warned that “Senior Assassin” can lead to dangerous misunderstandings, especially when water guns are painted to look real. The agency also noted that trespassing, disturbing the peace, dangerous driving and carrying an imitation firearm in public can carry legal consequences.
Incidents that show how quickly the game can escalate
In Portage, Indiana, police responded to a Planet Fitness on April 10 after a 911 caller reported a nervous man outside the business who appeared to be armed with a handgun. Officers later determined the 18-year-old was playing “Senior Assassin” with a realistic-looking water gun. Police said all 10 on-duty patrol officers, two off-duty officers and a sheriff’s deputy responded because the call sounded like a potential active shooter situation. The student was charged with felony intimidation.
The 18-year-old told CBS News he now fears his college scholarship could be in jeopardy due to the incident.
In Michigan, Davison Township Police Chief Jay Rendon told CBS Detroit that an officer had “milliseconds” to decide whether to fire after a student jumped out and sprayed him with a water gun while the officer was responding to a suspicious activity call. Rendon praised the officer’s restraint, but said the encounter came dangerously close to tragedy.
“He just had a fantastic action not to fire and shoot this kid,” Rendon said. “He had milliseconds to make that decision.”
On Long Island, Nassau County police said officers responded to three reports involving someone with a gun or a possible active shooter at area schools. In one case at Plainedge High School, a custodian saw two students with what appeared to be guns, prompting a 911 call and a school lockout. Police Commissioner Patrick Ryder told Newsday the incidents pull officers out of service and force schools and police to respond as though the threat may be real.
Police urge students to keep the game safe
Some police departments have taken a more measured approach, acknowledging that the game is a senior tradition while still urging students to use common sense.
In Whitman, Massachusetts, police told residents they may see high school seniors around the community with water guns and explained that they were participating in “Senior Assassin.” The department reminded students to respect private property and businesses and urged them to keep the game safe.
The warning signs police keep pointing to are specific: realistic-looking water guns, masks, dark clothing, students hiding near homes or businesses and games spilling onto school property.
A brightly colored water gun at a park among known participants is different from a student in dark clothing hiding near a home, business or school with a toy gun that looks real.
What students and parents should know
Police are urging parents to talk with teens before the game leads to a 911 call, criminal charge or dangerous confrontation.
The most common advice from law enforcement includes:
- Do not use realistic-looking water guns.
- Avoid masks, dark clothing or tactical-looking gear.
- Stay away from schools, businesses and private property.
- Do not play during school hours.
- Do not chase vehicles, drive recklessly or “ambush” people in parking lots.
- Make sure the game involves only willing participants.
- Consider playing in a controlled location, such as a park, and notifying local police ahead of time.
For students, the message from police is simple: The game may feel harmless, but the person calling 911 — or the officer responding — may not know it is a game.
As Portsmouth police warned in a recent advisory, “No cash prize is worth your life, a criminal record, or a tragic misunderstanding.”
