A second man has died from his injuries after shots were fired by police early Tuesday morning in Montreal's downtown core, near the corner of St-Denis and Ste-Catherine streets.

The 36-year-old was on his way to work at the Saint-Luc Hospital and was hit by a stray bullet.

Police were firing on a 40-year-old man who was seen wielding a knife. He died earlier on Tuesday.

The incident began when a police officer approached a man who was allegedly disturbing the peace and overturning garbage cans at 6:40 a.m. Tuesday.

Police say the 40-year-old man brandished a knife. There was a foot chase and the police officer fired shots about a block away from the initial encounter.

Quebec provincial police have taken over the shooting investigation. ((Steve Rukavina/CBC)) The man police were chasing was hit, as was the passerby.

Both men were rushed to hospital where 40-year-old Mario Hamel, a resident of a downtown homeless shelter, was pronounced dead.

The other man died Tuesday afternoon. His name has not been released.

Four police officers were taken to hospital to be treated for shock.

The investigation has been transferred to the Sûreté du Québec, which is the protocol when a Montreal police officer is involved in a shooting.

Police cordoned off the area and closed it to traffic for the investigation, but it has since re-opened.