Following the Madrid train bombings, Canadian security agents became aware of suspicious activity by Muslims in the Toronto subway system. We’re only hearing about it now because the Canadian government is being sued by one of the people who were investigated: CSIS monitored Toronto subway after Spain attack.

TORONTO — Just over a month after the train bombings in Spain claimed the lives of more than 200 people, Canadian security agents began investigating suspicious activities on Toronto’s subway system, fearing a similar attack, the Toronto Star reported Saturday. While security was enhanced and employees were warned to be extra vigilant last spring, it was observations from passengers that sparked at least two investigations.

One phone call to police claimed a man had kissed a book with Arabic writing on it, placed it inside a briefcase and then appeared to “purposively” leave the briefcase behind. When the passenger pursued him to ask about the briefcase, the man allegedly cursed and ran away, according to a description of the incident contained in court documents obtained by the Star.

Eight days later, on April 30, more passengers called police to say they had watched two men behaving in a “very suspicious manner” at the Bloor-Yonge subway station _ a major transfer point. They appeared to be taking covert video footage of the tracks.

One of those men, according to the court documents, was 38-year-old Kassim Mohamed.

And it was due to this behaviour that security agents became interested in him — not because he was filming the CN Tower for a tape he was making for his children, says the federal government.

The federal court documents filed Friday outline the government’s defence against a $1-million lawsuit launched by Mohamed that alleges his constitutional rights as a Canadian citizen were breached by the government’s investigation.