Minutes after he arrested someone on a robbery charge, an NYPD sergeant reportedly shot himself to death outside his Brooklyn police station last night.

According to the New York Post, the sergeant returned from the robbery bust and told a colleague he was going downstairs to get something. Thirty minutes later, police found the officer in his car, dead from what appeared to be a self-inflicted gunshot wound.

The sergeant, who was recently transferred to Brooklyn's 66th Precinct, was about to be promoted to detective, according to the New York Daily News' police source.

“People always say, ‘The signs, the signs,’ but there were no signs,” the source told the Daily News. “We’re all a little bit shell-shocked and saddened.”

A witness described the scene to the Daily News:

Efriam Baruch, 15, was on 59th St. near 16th Ave. when he said he heard two gunshots.

“I was down the block and heard two funny noises, like firecrackers exploding,” said the teenager. “I ran over to see what happened and I see all of this action, cops running out of the precinct to a car. It looked like someone was in the car.”

The teen added that he saw the dead sergeant hunched over near the passenger side of the car.

“It looked to me like (the officer) was laying down in the front of the car by the dashboard,” he said. “It’s a sad situation.”

Police have not released the sergeant's name or any information about a possible motive.

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