Police sources tell CTV News that a campfire made by homeless people to keep warm has caused millions of dollars in structural damage to the Pattullo Bridge.

The bridge will be closed for at least the next month.

Tom Pendergast, the CEO of TransLink, confirmed to CTV British Columbia that the wooden section damaged by the fire early Sunday would have to be demolished. He also said it would take at least a month and possibly as long as six weeks to fix.

He said Translink is responsible for the 72-year-old bridge and engineers were trying to decide the best way to repair it.

"That section is no longer usable. So the next thing is to basically demolish that wooden section," he said.

B.C.'s transportation minister, Kevin Falcon, said in an interview that a full replacement for the old bridge, announced last summer by TransLink, was still many years off. It will eventually be replaced by a toll bridge.

"I think this underscores that we are investing in important infrastructure like this. That's why we're building a new Pitt River Bridge. That's why we're building and moving forward with a new Port Mann Bridge," he said. 

"In the case of this bridge we've said to TransLink, 'look, we're prepared to help you.' We think we can go and work to get some federal dollars, some provincial dollars, and possibly even private sector dollars."

Falcon did not name a date for this, but said getting the current bridge repaired was a priority.

In the meantime, he added, commuters would need to "stretch out" the rush hour period between Vancouver and Surrey.

The fire was brought under control fairly quickly once firefighters were able to gain access to the area and to deal with downed electrical wires. However, it is expected that the site will smolder for several days.

The Pattullo Bridge is one of the main links in the Lower Mainland transportation system, carrying 80,000 vehicles daily between Surrey and New Westminister, said TransLink spokesman Ken Hardie. Its subsequent closure will cut off one of Metro Vancouver's most crucial travel arteries.

"Human activity was certainly a factor. Police are treating it as a crime, I believe," Hardie said.

He added TransLink was arranging a strategy to cope with traffic changes that would include more public transport.

"It will be a headache, and we are meeting to look at what we do about that and what we can do for transit in terms of providing extra capacity," he said.

Hardie said commuters must adjust their travel patterns starting Monday morning.

He advised motorists to leave earlier, and to avoid peak commute periods on the Port Mann and Alex Fraser Bridges. He said TransLink would also add extra SkyTrain capacity.

Up-to-date information on travel in the area will be available on the TransLink website.

With reports from CTV British Columbia's Renu Bakshi and David Kincaid.