Provincial police investigators said Thursday they have not yet interviewed four Montreal police officers involved in a shooting two days earlier that ended in two deaths, including a bystander who was on his way to work.

Guy Lapointe, a spokesman for Sûreté du Québec, said the four officers present during the fatal shooting would likely be interviewed sometime in the next few days.

He said it's normal to wait awhile before interviewing such witnesses.

Probe system criticized Police accountability in Quebec has come under fire in the wake of a handful of deadly police shootings in past years. One of the most high-profile cases involved Fredy Villanueva, an 18-year-old Montrealer who was shot dead in 2008 in a parkside confrontation with two local officers. In the Villanueva case, provincial police were asked to investigate the incident and concluded the Montreal officers acted appropriately. A separate coroner's inquiry into the Villanueva shooting has yet to release its findings. Since Villanueva's death, community activists and the province's own ombudsman have called for a major overhaul of the way police investigate injuries and deaths during their operations. Unlike a handful of provinces, including British Columbia, Alberta and Ontario, Quebec does not have an independent, civilian-run agency with the authority to investigate cases in which police actions result in injury or death. Under the current system, police investigators from one force probe incidents of civilian injury involving other forces. In a 2010 report, Quebec ombudsman Raymonde Saint-Germain urged the province to create a stand-alone, civilian investigative unit, instead of allowing police forces to investigate each other. "This is the only way to get the confidence of the population and to have a process that is credible and impartial," Saint-Germain said at the time.

"When you meet the major witnesses of a case, you want to be prepared, you want to know a bit of what might have happened and to be able to ask the right questions," he said.

Police were pursuing Mario Hamel, a homeless man who officers say was wielding a knife, through the downtown core on Tuesday when they fired, killing Hamel and Patrick Limoges, a 36-year-old hospital worker.

"Some officers were hospitalized, so that's also a factor," Lapointe said.

He said he didn't know yet if the officers involved had Taser stun guns at their disposal.

But Frank Phillips, who is with Ontario's Special Investigations Unit, the civilian body that looks into allegations of police misconduct in that province, said when it comes to interviewing police officers involved in a fatal shooting, the sooner, the better.

"As an investigator myself — the best evidence is the freshest evidence," he said.

Phillips said after a shooting in Ontario officers are designated as either subject or witness. Subject officers are those who pulled the trigger, while witness officers are others who were on the scene.

Patrick Limoges, 36, was killed by a stray police bullet Tuesday. ((Radio-Canada))

Although subject officers are not obliged to talk to investigators, Phillips said he would never wait a few days to talk to them.

"We ask for an immediate interview, or certainly we want to do it within 24 hours."

At Quebec's national assembly on Thursday, Public Security Minister Robert Dutil said he doubted the officers had the alternative to use Tasers.

"They don't have a lot of Tasers. You know, there's a big controversy on Tasers also, so the number was diminished in the past and their use was restrained," said Dutil.

The head of Montreal's police brotherhood, Yves Francoeur, also defended the officers involved in a statement released Thursday.

"Last Tuesday morning's events in downtown Montreal are sad and exceptional," said Francoeur. "[But] these events sadly reflect the harsh reality that Montreal police face every day."

On Wednesday night, protesters left graffiti at the scene of the incident including a crude outline of a corpse and the words "killed by the police" in French.

Meanwhile, Quebec provincial police returned to the scene of the shooting.

Investigators closed off St-Denis Street between René Lévesque Boulevard and Ste-Catherine Street Thursday morning to continue reconstructing the shooting.

Pierre Kirouac pays his respects at the site where hospital worker Patrick Limoges, 36, was killed. ((Paul Chiasson/Canadian Press))

"It's not unusual that we return to the scene. … We have ballistic experts and technicians … and their expertise will allow us to advance our investigation," Lapointe said Thursday.

He said investigators had also been approached by someone claiming to have more information about the incident, and investigators are trying to determine if the person's information is pertinent to the investigation.

Mother of victim speaks

In an interview with La Presse newspaper Wednesday, Limoges's mother said that she and her ex-husband are in shock.

"You can't expect me to believe that four police officers aren't able to disarm a man with a knife. There's no logic in shooting bullets like that," said Johanne Rocheleau in an article in the French-language newspaper.

Hamel, the man police say was brandishing the knife, also died when officers opened fire.

Rocheleau, who lives in Trois-Rivières, Que., told the newspaper police officers had met with family members at the hospital to explain what happened.

"They told us it was the first time that this had happened," said Rocheleau.

Another incident

There was an incident with a similar beginning but a different ending early Thursday in Montreal.

Police were called to the Hochelaga-Maisonneuve district where a woman was on the street with a knife.

Police described her as unco-operative and used a Taser on her. She was taken to hospital with minor injuries.