A policewoman-turned-“raging bull” was arrested Sunday after throwing her girlfriend into the plate-glass window of a Tribeca storefront, police sources and friends said.

NYPD Sgt. Tamara Beauzile (inset, Sunday night) was heading home from a downtown nightclub with several women when an argument broke out at around 4:30 a.m. Sunday.

“She was driving us all home. We were all drinking,” said one of Beauzile’s friends, who asked not to be identified.

The ladies then started arguing over directions.

“She wanted to take us one way, and we were saying we should go another way,” the pal recalled.

Then Beauzile, 43, a 21-year veteran of the NYPD’s applicant-processing division, allegedly turned on her gal pal, Samantha Douglas, who was also in the car, shrieking, “Bitch, I know where I’m going!”

“She punched her. She hit her [in] the car,” the friend claimed.

“She said, ‘Don’t let me be a cop tonight. Let me be a friend tonight.’”

Douglas, 38, tried to leave and hop in a taxi, but was turned away by the cabby because she was bleeding, the friend said.

When Douglas returned to Beauzile’s car to get her purse, the cop jumped out and started beating her, the friend said.

“She ran into her like a train with no brakes,” the friend said. “She just kept punching her.”

Beauzile then picked up Douglas and threw her into the window of Canal Furniture on Broadway near Walker Street, leaving a gaping hole.

“She picked her up and threw her into the glass,” the friend said. “She was like a raging bull.”

Both Beauzile and Douglas were injured by shards of glass.

“[Douglas] got kicked out of her shoes,” the friend added. “I put my hand up on her back and it was nothing but blood. She got stitches in her back.”

Beauzile was arrested and hauled off to the Fifth Precinct station house.

Douglas was treated at an area hospital for non-life-threatening injuries before she, too, was arrested and slapped with the same charges.

Douglas arrived at the station house Sunday afternoon with a swollen and bloodied face.

Police said Beauzile has not been charged with DWI, despite her friends’ claims that she was intoxicated.

“She’s got a temper,” said one of the friends. “Especially when she drinks.”

At Manhattan Criminal Court Sunday night, Beauzile was charged with assault, disorderly conduct and harassment. She was released on her own recognizance.

Douglas was awaiting arraignment Sunday.