A ticked-off driver pulled a loaded, stolen gun on a car — only to discover that it was full of plainclothes cops, a high-ranking police source said Sunday.

Glenn Grays allegedly pointed the .45-caliber gun out his window after cutting off the car carrying undercover detectives from the Brooklyn North Gang Unit on the westbound Belt Parkway on Saturday in Sheepshead Bay, according to the source.

Grays, a 31-year-old United States Postal Service employee, was arrested and charged with possession of a firearm and menacing, the source said.

This is not the first time Grays has had a run-in with undercover cops.  In 2016 the then 27 year old letter carrier was arrested after yelling at a car full of plain clothed NYPD cops who nearly struck him as he delivered mail.

Source: Raging driver pulled gun on car full of undercover cops

Video: NYPD arrests on-duty letter carrier for shouting at them — leaves mail truck unattended

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