Const. James Forcillo is currently being investigated following the shooting of teenager Sammy Yatim on a TTC streetcar. Forcillo is a 6-year veteran of the Toronto police force.

Ontario's police watchdog has laid charges in a Toronto streetcar shooting that resulted in the death of 18-year-old Sammy Yatim.

Yatim was shot while brandishing a knife on board an empty streetcar last month, while in a standoff with police. As many as 23 police officers were at the site of the shooting, according to the Ontario Special Investigations Unit.

Video of the incident captured the moment when nine gunshots were fired, including several once Yatim had collapsed to the ground. The SIU allege a conductive energy device was also used on the victim while he was being subdued.

On Monday, the SIU announced a second-degree murder charge would be laid against suspect officer Const. James Forcillo.

"A warrant was issued this morning for the arrest of TPS Constable James Forcillo," a statement reads.

"Because the arrest warrant was just issued, Cst Forcillo has not been arrested at this point. An updated news release will be issued and tweeted as soon as there are any material developments."

The Yatim shooting has been a hot-button issue for the Toronto Police Service, thanks in part to the graphic nature of his death and the awareness raised by several publicly released videos.

Chief Bill Blair has promised the public that he was taking the incident seriously and tasked a retired judge to conduct an oversight investigation into the force. Ontario's ombudsman has launched a separate investigation focused on de-escalation tactics used by Ontario police forces.