MONTREAL - A knife-waving man who attacked police was shot dead Thursday in Montreal -- the fourth fatal shooting involving the city's officers in eight months.

Montreal's police department said officers were called to an apartment in the city's east end, where a man had apparently been threatening to kill himself.

A witness, who lives in the same building, said the man hit police with his knife, forcing frightened officers to try and back off in a cramped hallway.

"It was like he was having an overdose or something," Alen Abdelghani told reporters.

"He didn't hear anything, he was crazy. He came out with his knife."

Four people have been shot and killed during three separate Montreal police interventions since last spring.

The previous incidents set off debates about whether more police should carry stun-guns, whether officers are adequately trained to handle people suffering from mental illness, and whether police shootings should be investigated by other police.

Quebec law calls for another police force to investigate incidents that cause injury or death involving officers, so this file was turned over to the provincial department.

A spokesman for provincial police said the man shot Thursday was 30-year-old Jean-Francois Nadreau.

Sgt. Claude Denis said Nadreau was shot once after he threatened an officer at the scene with a knife. Due to the ongoing investigation, Denis declined to confirm whether the man attacked police.

The building's owner, Samira Harfoush, told La Presse that she was awakened early Thursday morning by loud noises coming from the man's apartment, including doors slamming, music and screaming.

"I saw police shoot (him)," said Harfoush, who had gone downstairs to see what was going on after officers had arrived.

A spokesman for the ambulance service said Nadreau was declared dead at the scene.

"Our paramedics found a man, in his 30s, on the ground with one bullet in his thorax -- no sign of life," Robert Lamle told reporters in the city's gritty Hochelaga-Maisonneuve district.

Lamle said two women were taken to hospital to be treated for shock. He believes one of the women is Nadreau's partner.

Fatal shootings involving police have attracted significant attention in the city in recent months.

Last June, an incident in which Montreal police shot and killed two men -- including a bystander on his way to work at a nearby hospital -- made national headlines and prompted an angry anti-police demonstration.

Passerby Patrick Limoges and Mario Hamel, a mentally ill man who lived in a downtown shelter, were both hit by police bullets in the city core. The police department said officers were called as a knife-wielding Hamel tore open garbage bags and tossed trash onto the street.

Witnesses said Hamel, 40, was shot after officers pepper-sprayed him and repeatedly pleaded with him to drop his knife.

The 36-year-old Limoges happened to be walking on the other side of the street when he was hit by a bullet that had missed its intended target.

In January, police fatally shot a 34-year-old homeless man named Farshad Mohammadi during an altercation at a subway station.

Police said Mohammadi used a knife to attack officers, including one who suffered cuts to the head and upper body. The other was treated for shock.

The co-chair of a Montreal-area police-training program said students receive significant schooling in crisis intervention and how to manage people in emotional distress.

Jim Anderson, a former Montreal police officer who now works at John Abbott College, said police are also trained to stay out of a suspect's striking range while they try to calm the situation.

"Now, this you can do with someone who hasn't been heavily drinking, on psychoactive drugs, or has a mental problem which inhibits his ability to interpret reality," Anderson said.

"Once the suspect... closes that safety gap (and) slashes and wounds a police officer -- all things are out the window."

Anderson said he supports the use of stun guns, such as the Taser, as long as officers are thoroughly trained in how to use them -- and to not overuse them.

Montreal police are equipped with fewer Tasers than other major Canadian cities, something Anderson believes should change with the goal of saving lives.

A spokeswoman for Montreal police said Thursday that the force has added more Tasers in recent months, but she could not immediately provide further details on how many have been purchased or how they're being used.

"Although (the Taser) is not 100-per-cent safe, it's a hell of a lot safer than bullets," Anderson said.

He added that other non-lethal police tools used elsewhere, such as nets and beanbag guns, could also be considered for Montreal's force.

Without options, police have to rely on bullets, Anderson said.

"Unfortunately, line officers are called to make those kinds of nasty decisions and I'm sure no one feels good about that, no matter the circumstances."