Montreal police are looking for witnesses to an attack in downtown Montreal that killed a man.

Police say that on the night of July 22, three men assaulted a 33-year-old homeless man on Mountain St. between Sherbrooke St. and De Maisonneuve Blvd.

The victim was taken to hospital and he never recovered from his serious injuries. Police say he died on August 11, three weeks after the attack.

The suspects are described as three black men in their thirties, all more than 1.8 m (six feet) tall.

The three men spoke English, and one of them had dreadlocks.

The men were seen fleeing the scene in a recent model Honda sedan with tinted windows and mag wheels.

Montreal police set up a command post at Mountain and De Maisonneuve Wednesday starting at 4 p.m. in hopes of finding someone who saw the attack or the suspects.

“The origin of this conflict is still unknown right now,” said Montreal police spokesperson Manuel Couture. “We don’t know why it happened. We don’t know if they just crossed the street together, if they just made eye contact. We don’t know exactly why it happened. That’s why we’re here.”

Anyone with information is urged to call Info-Crime at 514-393-1133.