PLAINVIEW, N.Y. (CBSNewYork) – At least five people are hospitalized after a chaotic chain of events led to a multi-car accident on Long Island.

Police say it started when a 25-year-old man was cleaning his gun at his home and it accidentally went off, hitting a 17-year-old in the neck.

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The 25-year-old was then driving the teen to the hospital when police say they got into an accident with three other cars in Plainview around 7:15 p.m.

They were on Manetto Hill Road, about to make a left at the intersection on Old Country Road, when they somehow collided with an oncoming car head-on.

The car it hit spun out, slamming into two more cars. One of those vehicles was being driven by an off-duty Nassau County police officer heading home after her shift.

“I was stopping at the red light, I heard a big crash, I kinda blacked out and then the car over there spun into mine,” accident victim Joey Sara said.

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“As soon as it happened, she got out of her car, told me she was a cop, she asked for my phone then called her precinct and she responded to the other person who was hurt cause I was fine.”

That police officer jumped into action right away, providing critical aid to the other victims.

“Her training kicked in. Even though she was injured, she administered aid to other people, she called 911, secured the scene, made sure everyone was cared for and nobody left the scene until police arrived,” Lt. Richard LeBrun of the Nassau County Police Department said Thursday night.

Officials are investigating what caused the crash, but say everyone involved suffered non-life-threatening injuries.

Police are also probing if the gun was a legal firearm and who exactly is responsible for this crash. At this point there are no arrests.

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