NYPD: Three cops 'violently attacked' by protesters on Brooklyn Bridge. One injured officer is chief of the department.

The New York City Police Department said three officers were "violently attacked" and seriously injured by protesters on the Brooklyn Bridge on Wednesday.

An individual is seen striking officers with what appears to be a caneImage source: NYPD News video screenshot

Terence Monahan — the chief of department and NYPD's highest-ranking uniformed officer — said he was cut and sprained a finger during the altercation on the Manhattan side of the bridge, WNBC-TV reported.

Image source: NYPD News

Two other officers, a sergeant and a lieutenant, were taken to a hospital for stitches, WNBC added.

Image source: NYPD News

Ironically, Monahan was one of several police officers who took a knee with George Floyd protesters in a headline-grabbing moment in early June, the station reported in a separate story.

Police told the station 36 people were arrested Wednesday, and most appear to have been involved with Occupy City Hall demonstrations; none were part of "Stop the Violence" rallies calling for an end to gun crimes in the city, WNBC added.

What went down?

The station said video shows a group of officers attempting to detain a man on the bridge before another man runs over and uses what appears to a cane to smash officers on their heads:

"Three officers violently attacked by protesters crossing the Brooklyn Bridge," the tweet from NYPD News reads. "The officers sustained serious injuries. This is not peaceful protest, this will not be tolerated."

Another video shows a pair of cops helping one injured officer away from the scene:

According to WCBS-TV, peaceful unity marchers began to cross the Brooklyn Bridge and were met by counterprotesters walking into traffic and sitting down in the roadway, blocking vehicles on the bridge.

Image source: WCBS-TV video screenshot

Image source: WCBS-TV video screenshot

The WCBS images of counterprotesters on the bridge appear to be the same location where officers were physically attacked. The counterprotesters told WCBS the unity march was too supportive of police.