OTTAWA (Reuters) - Montreal police are searching for four suspects after smoke bombs at least three subway stations disrupted service for thousands of commuters in Canada's second-largest city during the morning rush hour, police said on Thursday.
City police declined to say why the four individuals were under suspicion, but they released photos, provided by a subway passenger, showing three women and a man riding in a train.
Earlier on Thursday, officers found three devices after receiving dozens of calls about dense smoke in several underground stations. Thousands of commuters were stranded, but nobody was hurt.
Subway service in the city - the commercial capital of the mainly French-speaking province of Quebec - was fully restored around midday.
Quebec Premier Jean Charest, who is embroiled in a high-stakes battle with university students over proposed tuition increases, called the acts "unjustifiable."
Neither Charest nor the police have linked the attacks to the student protestors, who have taken to the streets of Montreal in recent weeks to voice their opposition higher fees.
"Hopefully we'll find the culprits and find out who did that," Charest said.
The rallies have been mostly peaceful, but sporadic violence has flared. The students have shown little sign of standing down even after the Liberal provincial government offered them to compromise.
Reporting By Louise Egan; Editing by Frank McGurty