NEW YORK (CBSNewYork) —  Police officers joined community leaders for a show of solidarity across the city Monday night, in the wake of the shooting that killed Officer Randolph Holder last week.

Prayer vigils were held outside precinct houses around the city, each of them for a total of 37 minutes. There were 33 minutes for each year of Holder’s life, and four for each of the NYPD officers killed in the line of duty over the last year.

READ MORE: NYPD: Mother Throws 4-Week-Old Daughter, 2-Year-Old Son Out Window Before Jumping Out Herself

Police Commissioner Bill Bratton tweeted photos of several of the events.

“This gun violence is a pariah in our community and it has to stop but we also have to say that our police officers are human,” said community advocate Tony Herbert, who came up with this show of support. “We have to show them the support that we can.”

“You don’t stand alone,” said Clark Pena, a community leader in East Harlem. “Law enforcement is not the enemy. We have to work together because we have to live together.”

Tyrone Howard, 30, is charged with first-degree murder and robbery in connection with Holder’s death. Police said he stole a bike before fatally shooting Holder in the head Tuesday night.

MORE NEWS: 145th Westminster Kennel Club Dog Show Underway In Tarrytown

Detectives said a gun found in the Harlem River on Sunday, and tests confirmed a day later that it was the same weapon used in the killing.