Police have issued a Canada-wide-warrant for a 28-year-old who is wanted for second-degree murder after a man was stabbed Saturday morning.

Police are looking for Vimalathas Mohanarajah after they found Ajiganth Mahalingam wounded in an apartment building shortly before 6:30 a.m.

A  post-mortem conducted on Sunday revealed the cause of death was "a stab wound to the heart and aorta" police comfirmed.

The 27-year-old was allegedly stabbed after a dispute erupted at a birthday party -- and police said the victim and the accused definitely weren't strangers.

"(They) were well-known to each other. They've been close friends for several years," said Det. Sgt. Terry Wark.

Wark also said an argument with a woman could have been a catalyst for the alleged murder.

"The altercation in the apartment itself was a dispute with a female which escalated."

The victim was discovered in a hallway on the 17th floor of the public housing development on Kingston Road, just west of Morningside Avenue.

He received emergency treatment at the scene, but had no vital signs. The Toronto man was then was taken to hospital, where he was pronounced dead, police said.

The suspect doesn't have an address, but he's known in the neighbourhood -- and by the authorities, CTV's Jim Junkin reported.

Police are encouraging him to contact homicide detectives or get counsel and turn himself in.

Anyone with information is asked to contact Toronto police at 416-808-7400, Crime Stoppers anonymously at 416-222-TIPS (8477), or online atwww.222tips.com.