Video shows robbers attacking off-duty cop in the Bronx

NEW YORK - A police officer who was robbed and beaten while he was off-duty remains in critical condition at Jacobi Medical Center in the Bronx. 

Four men ambushed the officer on Olmstead Avenue in the Unionport section early Tuesday morning, the NYPD said. They beat him and stole his phone, car keys, and wallet, police said.

A law enforcement source identified the cop as Police Officer Muhammed Chowdhury, 48, an 18-year veteran who works in Manhattan. He suffered a fractured skull and brain bleeding.

Fox 5 News obtained video from a private security camera shows several men running up to Chowdhury and attacking him.

Also, New York City police released a video showing four men getting out of a black sedan. Investigators believe these men attacked Chowdhury and may be behind a string of robberies in the city. 

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In many of those robberies, three individuals approached a victim while a fourth person stayed in the car. A black sedan was the most commonly used car in all of these attacks. 

This week, the head of the Police Benevolent Association, the union that represents rank-and-file officers, called for justice.

"While we pray at our injured brother's bedside tonight, police officers across this city are searching for the cowards who did this to him. Make no mistake: we will find them," PBA President Patrick Lynch said in a statement. "But we will need the rest of the justice system to step up and do its job, too. This is what happens when our leaders refuse to hold criminals accountable — not even a police officer can walk these streets safely."