June 8, 2020 | 7:54pm

Police officers tackled, punched and arrested a bike protester during a Black Lives Matter bike ride in Brooklyn Saturday night, video shows.

Pierce McCaffrey, 22, of Bed-Stuy, told The Post cops tackled and cuffed him after he intentionally slow-rolled in front of an NYPD van at around 7:40 p.m. in downtown Brooklyn — 20 minutes before the city’s curfew went into effect.

“I was going pretty slow, and he sirened at me, but I didn’t move. Then they hopped out and started hitting me, and they tackled me. I was in the cop car within a minute,” said McCaffrey, a recent NYU grad.

Video originally published by Streetsblog shows the hoard of bike protesters edging up Nassau Street to the right of a line of parked cars just north of Gold Street. Sirens suddenly sound, and McCaffrey can be heard screaming “What the f–k!”

The video then shows four cops chase McCaffrey, tackle him to the floor and start swinging.

“Don’t resist, bro!” the cameraman yells as McCaffrey takes multiple blows.

“I’m not!” he responds.

McCaffrey said cops kept him in jail for two hours — before releasing him with a disorderly conduct summons for cursing them out while he was on the ground.

NYPD did not immediately return a request for comment.

Additional reporting by Tina Moore