A Toronto police officer has been charged with second-degree murder in connection with the fatal shooting of a teenager aboard a streetcar last month.

An arrest warrant has been issued for Const. James Forcillo, Ontario’s Special Investigations Unit said in a statement Monday morning. Because the warrant was just issued, the agency said, Forcillo has not yet been taken into custody.

The statement from the agency said that SIU director, “Ian Scott, has reasonable grounds to believe that a Toronto Police Service (TPS) officer committed a criminal offence in relation to the shooting death of 18-year-old Sammy Adib Yatim in July of 2013.”

The SIU is an independent body that probes incidents of serious injury or death involving police officers.

Yatim, 18, was shot and killed in the early morning hours of July 27 during a standoff with police. Local surveillance video and cellphone images taken by passersby showed Yatim, who was holding a knife, pacing back and forth on the empty streetcar as police shout, “drop the knife.” Then, over the course of 13 seconds, nine shots ring out. A Taser was also used during the incident.

Forcillo was suspended with pay while the SIU conducted its investigation.

Earlier this month, Ontario’s ombudsman announced he was launching a formal investigation into provincial guidelines issued to police for de-escalating conflict situations.

Andre Marin said his investigation will look at how police forces across the province train officers to respond to conflict situations, and whether the Ministry of Community and Correctional Services should consider implementing a province-wide standard.

Marin said his probe will also look at what became of recommendations that came out of coroners’ inquests and other reports into police shootings dating back to 1994. The investigation will take between six and 12 months.

Yatim’s shooting also sparked an online petition calling for criminal charges to be laid. Within days, the petition had more than 30,000 signatures.