The gunman behind the shooting in Toronto's Greektown neighbourhood, Faisal Hussain, was allegedly from Pakistan's Jhelum.

According to sources, Toronto Police, Canadian Security Intelligence Service (CSIS), and Royal Canadian Mounted Police (RCMP) are looking into his past, which include his residences in Afghanistan and Pakistan.

As per a law enforcement source, Hussain's files, which are presently being reviewed by the police, have sparked concern that the shooter has expressed support for a 'pro-ISIL' website. The 29 year old shooter had been previously spoken to about his online activities and the RCMP, Toronto Police and Ontario Provincial Police had expressed an interest in the alleged shooter.

Meanwhile, Hussain's family members have expressed their grief in a media statement, saying that the shooter struggled with psychosis and depression and medication and professional intervention were unable to cure him. "Our hearts are in pieces for the victims and for our city as we all come to grips with this terrible tragedy. We will mourn those who were lost for the rest of our lives," they said.

Earlier on Sunday, a shooter opened fire in front of a restaurant in Toronto's Greektown neighbourhood, injuring 13 and killing two. Canadian Prime Minister Justin Trudeau has condemned the incident calling it a "terrible tragedy".