The Green Line was shut down Friday and the area evacuated after cracks were discovered in a large slab in the city’s underground corridors, The Montreal Gazette reported. The Montreal underground connects buildings and transportation, providing protection from the bitter winter cold.
"We're going to make sure the structure is reinforced before we reopen anything," Mayor Gerald Tremblay said.
Engineers do not know how long the slab has been cracked. Two fissures were discovered after employees in the basement level of the Bay noticed water seeping in from a nearby Metro station.
The closing off of the Green Line and blocking of streets caused massive traffic jams Friday afternoon.