Winnipeg police have a suspect in custody for the killing of a man Thursday night.

It's believed the victim was stabbed in the heart. Paramedics rushed him to hospital in critical condition where he was pronounced dead.

Officers and emergency crews were originally called to the 1300 block of Notre Dame Avenue around 11:30 p.m. on April 12 for a report of an injured man.

Gerry McCasky said he watched as people tried to save his friend's life.

He identified the victim as Mike Parker. McCasky said he saw his friend lying bleeding on the pavement.

"I was kind of devastated. I don't know what to say – I'm still stunned to tell you the truth," he said.

Police taped off the house the victim shared with his mother, but the majority of the investigation focused on the parking lot of the Thriftlodge Motel across the street.

"I'd seen that trail of blood going…towards the bus stop and it was all marked with the (evidence) numbers," said Jenny Land, who saw police investigating.

Shortly before the killing, Land remembers hearing what sounded like a fight coming from the Notre Dame Avenue house.

"They were screaming and cussing," said Land.

Police weren't saying much about a possible motive on Friday, just that some progress had been made in the investigation.

"I can tell you I just got word we do have a suspect in custody," said Const. Natalie Aitken from Winnipeg police on Friday afternoon.

While a suspect was in custody, charges had not been laid April 13.

The Notre Dame Avenue killing marks Winnipeg's 12th homicide of 2012.

Police continue to investigate and are asking anyone with information to contact homicide investigators at 986-6508 or Crime Stoppers at 786-8477.

 - with a report from CTV's Stacey Ashley