MONTREAL - The Quebec government says it had no choice but to close a major bridge in Montreal because a company repairing the structure unintentionally damaged 40 reinforcement bars.

Transport Minister François Bonnardel is promising to carry on repair work 24 hours a day, seven days a week to reopen the Île-aux-Tourtes bridge on a highway linking Montreal to Ontario.

The Transport Department closed the bridge Thursday during the afternoon rush hour, and Bonnardel said today he doesn’t know when it will reopen but he doesn’t foresee a long-term closure.

Bonnardel told reporters the damage was caused by human error, but he didn’t want to blame the construction company hired to repair the bridge, which opened in 1965 and is scheduled to be replaced by 2027.

He says reinforcement bars were added to the aging structure in 2012, and 40 of them were recently damaged when construction workers drilled boreholes as part of their repairs.

The Île-aux-Tourtes bridge links the western tip of the Island of Montreal with the town of Vaudreuil-Dorion, Que., and is used by 87,000 vehicles a day, 10 per cent of which are trucks.

Bonnardel says the bridge was secure but was damaged by human error.

“I don’t want to blame anyone, but we are working with humans,” he told reporters. “We are working with a contractor. We have a good contractor that is doing good work.”

He added that he’ll be able to provide a clearer timeline for reopening the structure in the next few days and acknowledged that the closure has created major traffic headaches.

“I can’t conceive it will be closed over the long term, and I am doing everything in my power to reopen this as fast as possible,” he said. “It’s true that we can’t give you a tight timeline; we are following this hour by hour.”