Toronto police are investigating three separate homicides that happened in the span of five hours Sunday morning.

In a bizarre incident in the city's east end, an attacker chased a man with a car then ran over him twice before getting out of the vehicle and stabbing him with a machete.

Police said the two men had been involved in some sort of dispute, but did not disclose details.

They found the victim on a lawn in the Longbow Square and Huntsmill Boulevard area near the Warden and McNicoll avenues intersection in Scarborough at about 10 a.m.

The man was rushed to hospital where he was pronounced dead. His name has not been released.

Earlier in another part of Scarborough, a father found the lifeless body of his son in the family's backyard just before 7:30 a.m.

The unidentified 22-year-old was pronounced dead at the scene.

Police cordoned off the home on Bridlington Street south of Ellesmere Road for several hours. There are no suspects, police said.

Officers also responded to a call at 5:30 a.m. in downtown Toronto after a man was found shot in the head in a Parkdale building. It happened at a King Street West rooming house near Elm Grove Avenue.

The shooting death may be linked to the drug trade, police said.

The violence over the weekend raised the number of homicides in the city this year to 50.