An arrest warrant on a charge of second-degree murder has been issued for 24-year-old Mohamed Ibrahim Sail in connection with the death of Jeremy Cook.

London police say the Canada-wide warrant was applied for Monday, and the whereabouts of the Calgary man - who is considered dangerous - are unknown.

Cook, 18, was shot and killed in a northeast London parking lot on June 14, after tracking his lost cellphone to a vehicle to the area.

Police had previously issued an arrest warrant for 23-year-old Muhab Sultanaly Sultan, also of Calgary, on a charge of second-degree murder in the case.

About a week later, Sultan was found dead in Ottawa's Rideau River on June 27, shortly after an interaction with local police, and his death is under investigation by Ontario's Special Investigations Unit.

Officials also say a third person seen leaving the Huron Road and Highbury Avenue area just before the shooting has been identified but has not cooperated with police.

Anyone who sees Sail is asked not to approach him, but to instead call police immediately.