The family of Sammy Yatim expressed relief Monday that a Toronto police officer is facing a charge of second-degree murder, following the fatal shooting of the 18-year-old on a streetcar last month.

A statement issued from Ontario’s Special Investigations Unit — the province's police watchdog — says the actions of Const. James Forcillo in the downtown Toronto incident this summer justify a charge of second-degree murder.

Forcillo, the officer who fired the shots, had been suspended from duty during the investigation.

The SIU statement said Forcillo will surrender Tuesday, when he is also due to appear in court. The SIU statement said the location of the arrest won't be disclosed because Forcillo has been the subject of threats.

Late Monday afternoon, the Yatim family issued a statement saying they were "relieved" to learn that the SIU had recommended charging the officer.

"We have been waiting patiently and co-operating with the police investigation and want to hold accountable all those responsible for Sammy’s death," said the statement that was sent to media.

Sammy Yatim, 18, was fatally shot by police aboard a Toronto streetcar in July. His sister Sarah tweeted this picture on Saturday with the caption, 'Never forgotten ... At least not to me.' (Twitter)

But the Yatim family said they also want the SIU to look into the actions of other officers who were present at the time of the shooting. The statement followed a tweet that Yatim's sister had sent out earlier in the day, shortly after the news broke that the officer had been charged.

"The SIU charged the cop with 2nd degree murder!!! Good morning JUSTICE," the tweet from Sarah Yatim said.

The SIU investigates all incidents involving police that result in death or serious injury, or when allegations of sexual assault are raised.

The Canadian Press reported Monday that the SIU has investigated more than 100 firearm deaths since 1990. Forcillo is just the third officer to be charged with second-degree murder since the SIU was created.

Teen shot on streetcar

Yatim was on a streetcar stopped on Dundas Street West, near Bellwoods Avenue, when he was shot dead in the early minutes of July 27. Witnesses have said that Yatim was holding a knife while inside the empty streetcar.

Const. James Forcillo is facing a charge of second-degree murder in Yatim's death. (Movember.com/Canadian Press)

Nine shots can be heard on cellphone videos that captured the incident, following shouts for Yatim to drop a knife. The final six shots appear to come after he had already fallen to the floor of the streetcar.

The shooting was recorded on video by several sources and viewed more than a million times on YouTube, galvanizing public anger and leading to a street protest that drew hundreds of people to the site of the shooting.

In addition to the SIU investigation, Toronto police Chief Bill Blair has said retired justice Dennis O'Connor will lead a separate review of police procedures, use of force and police response to emotionally disturbed people in the wake of Yatim's death.

Ontario ombudsman André Marin has also launched an investigation that will probe what kind of direction the provincial government provides to police for defusing conflict situations.

The Toronto Police Association has urged the public not to jump to conclusions in the case, and told CBC News it is disappointed but not surprised by the charge against Forcillo.

Mike McCormack, the association president, said that the aftermath of the shooting has been difficult for the officer and his family.

"It's very stressful for him and his family and it's definitely taking its toll on him and his family," he told CBC News in an interview on Monday.

Forcillo has spent six years as a member of Toronto's police force, splitting that time as both as a uniformed constable and at court services at Old City Hall.

On Monday afternoon, Joseph Nazar, a friend of the Yatim family, said that he viewed the charge against Forcillo as a "first step" in the judicial process that is still unfolding.

Nazar said that Yatim's death was unnecessary. The shooting cut short the teenager's opportunity to live the Canadian dream, he said.