MASSAPEQUA PARK, NY (PIX11) – Some eyewitness are now saying that a Nassau County police officer was shot and killed by an MTA officer after a civilian yelled “gun,” according to James Carver, the president of the Nassau County Police Benevolent Association.

Plainclothes Special Forces Officer Geoffrey J. Breitkopf, 40, was shot and killed Saturday by MTA officer Glen Gentile in the front yard of a house where an armed suspect, 21-year-old Anthony DiGeronimo, had barricaded himself inside.

"Friendly fire is when there is situation happening where you are exchanging fire with the bad guys, this was nothing (like that), the scene was already over with . . . it was in a clean-up mode," said Carver.

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Authorities are still investigating how it was possible that the friendly fire incident happened, considering that Breitkopf was shot roughly ten minutes after DiGeronimo, police said.

Around 8 p.m. police received a call of an armed, suspicious person walking near Front Street, and multiple officers responded to the scene.  Two uniformed officers chased DiGeronimo inside his house, where he barricaded himself in a room. 

The officers shot and killed DiGeronimo after he opened the door and lunged at the officers with “Rambo-style” knives in both hands, police said.

An unidentified MTA officer that had also responded to the scene saw officer Breitkopf, a 12-year veteran, in front of the house dressed in street clothes holding a rifle. 

It was at this moment that officers on the scene reported a civilian yelling “someone’s got a gun,” according to Carver.

MTA officer Glen Gentile, who is now on medical leave, shot Breitkopf in the head, killing him. 

Officer leaves behind his wife and two young sons, 3 and 6 years old.

A funeral will be held for the 12-year-veteran this Friday.