Winnipeg police were combing a residential neighbourhood Sunday, searching for a suspect who shot two men and a teenage girl in what investigators believe were random shootings.

"It seems to be random shootings," Const. Jason Michalyshen, a spokesman for Winnipeg police, said in a media briefing. "We don't know where this individual is at this point."

Two men were killed and the young woman was in critical condition after the shootings Saturday evening near a housing complex in Winnipeg's north end.

Police say a 13-year-old girl was shot first and seriously wounded. Fifteen minutes later, an adult male was gunned down and killed a few blocks away, followed 20 minutes later by the fatal shooting of another man in a third location.

Michalyshen said officers are looking for a person who may be male, aboriginal, in his twenties, wearing dark clothing and between 5'8 and 6'0 in height.

One witness described seeing a man riding down the street on a mountain bike "looking like a ninja."

Police have not ruled out the possibility that there may have been more than one person involved, could not verify if the suspect was on a bicycle -- as some witnesses told investigators -- or on foot.

They say the three victims were shot by a large-calibre firearm, but added that no weapon has yet been recovered.

Michalyshen could not even say definitively that the shooter was male, or confirm that the three shootings were linked. He said detectives have called in a crime analyst to help them make sense of the attacks.

"It's to attempt to bring a link, if possible, to three incidents," Michalyshen said. "We haven't been able to do that at this point."

Michalyshen said it appeared the victims were all confronted on the street and they did not know each other.

Police officers were going door-to-door Sunday searching for clues in the shooting, with heavily-armed tactical squad officers nearby.

Michalyshen said the three shooting scenes and the continuing hunt for a suspect has stretched police resources.

"We have officers who have been working around the clock and will continue to work around the clock with respect to these three incidents," he said.

In the wake of the shootings, police were warning people living in the neighbourhood, a low-income area which has been plagued by drugs and gang violence in the past, not to open their doors to unexpected visitors and not to investigate if they hear something suspicious outside.

The police warning left the streets nearly deserted Sunday in the area where the shootings occurred.

But Michalyshen said that while citizens should be cognizant of their safety, they should not be in a state of terror. "We're not about to create panic," he said.