Fare-beating anti-police protesters lopped the arm off a metal subway turnstile when they stormed a Bronx subway station on Friday, according to a video posted online.

The footage — tweeted by agitator group Decolonize This Place on Sunday — shows at least a dozen activists march into the E. 149th Street and 3rd Avenue stop. One portion shows a three-armed turnstile with one of its limbs shorn off just inches from the base.

“JUST RELEASED Turnstile hopping and cutting came When the massive FTP 2 cat march splintered into three one contingent took the Madison Avenue Bridge into the BX. This what happened at 3rd Av. and 149St subway stop. #evade #ftmta #ftp #decolonizethisplace #swipeitforward,” boasted the group, which bills itself as an “action-oriented movement on Indigenous struggle, Black liberation, Free Palestine, workers, de-gentrification, and dismantling patriarchy.”

It was not immediately clear how they cut the metal arm.

The edited video bookends with FTP — “F–k The Police” — on the screen as the group appears to protest the increased patrols in the subways.

Law enforcement in the subways has become a hot-button issue, with scores of demonstrators marching in recent days against the arrest of subway vendors and Gov. Andrew Cuomo’s plan to deploy 500 new cops to police fare-beating and other crimes.

Police sources claimed city politicians are stoking anti-cop sentiments.

“It’s absolutely disgusting. Our politicians should be ashamed of themselves. We need to get these clowns out of the office and get someone with balls to take back this city. There is going to be a day when this city has a savior and the cops are going to be unleashed and these advocates and protesters are going to have another thing coming,” one particularly angry source fumed.

Cops arrested dozens of protesters as they chanted “fare-free NYC” and “f–k the police” while marching in Upper Manhattan on Friday, but it was not immediately clear whether anyone was collared for the turnstile vandalism.

The gate was repaired by Sunday, an MTA spokesman said.

“Vandalism of transit property is not only unacceptable, but illegal — ultimately costing all New Yorkers, while diverting funds that could be used for reliable transit service,” said authority rep Tim Minton. “Fare evasion is a $300 million a year problem and we expect all New Yorkers to pay their fair share when riding our system as is required by law.”