'Shots fired,' NYC officer yells after his partner is gunned down in ambush (AUDIO)

A New York City police officer was fatally shot early Wednesday after being ambushed inside a mobile command post parked in the Bronx, The Associated Press reported.

The shooter, killed by police a block away after he pulled out a revolver, was an ex-convict who had reportedly written online rants about how he was treated in prison and about how police get away with killing people.   

Thirty-four-year-old Alexander Bonds ambushed officer Miosotis Familia while she sat in the front seat of a police mobile command vehicle writing notes, AP reported.

It was about 12:30 a.m. when he reportedly walked up and fired a single round through the passenger-side window, striking Familia in the head.

“PO Miosotis Familia has been assassinated in an unprovoked attack on cops assigned to keep NYers safe,” Police Commissioner James O’Neill tweeted.

Familia’s partner can be heard frantically shouting to dispatch about the “shots fired, shots fired” in audio obtained by the AP.

One witness described the scene to a reporter from the Daily News.

“All of a sudden there was all this running and stuff going on, and I look out, probably 40, 50, 60 cops screaming, ‘Call a paramedic, clear the block!’” he said. “It looked like there was a riot going on, and two seconds later I hear gunshots, ‘Bam, bam.’”

Attorney General Jeff Sessions called the shooting “cowardly” and “unprovoked.”

“This murder in cold blood is a tragedy, and sadly it is the latest in a troubling series of attacks on police officers over the past two years,” Sessions said in a statement. “These attacks must stop and we must honor the service of every law enforcement officer and the memory of those we have lost in the line of duty.”