Around 7 p.m. Thursday, crews were battling a massive fire on I-85 northbound just south of Ga. 400 when a section of the highway collapsed, officials said.

Fire officials extinguished it on Thursday night after it burned for more than an hour, fire officials said.

» RELATED: 5 things to know about the fiery I-85 bridge collapse

Capt. Mark Perry of the Georgia State Patrol said terrorism is not suspected, but they don't know what started the fire.

At first they thought it was a car burning, but later said it could have been something else, Perry said.

Troopers based in Atlanta were working about 7:45 p.m. to get cars on the interstate turned around.

» RELATED: PHOTOS: Atlanta I-85 fire -- Highway bridge collapses near Piedmont Road

"Atlanta Mayor Kasim Reed said late Thursday he’s spoken with the FBI “and at this time there’s no evidence of terrorism” and that city officials will be working to assess the bridge throughout the night.

“This is as serious a transportation crisis as we could have. The governor has been leading and we have been acting on it. Our primary concern, first and most important, is that no one has lost their life. And as we stand here right now, we think that’s the situation.”

“It’s going to take some time to do a thorough assessment to determine what damage has been done to that section” of the bridge, Reed said. He said the city is working with the state to secure the area, but is wary of moving too quickly “because there is a possibility you could have a further collapse.”"

A large fire has collapsed a section of I-85 in Atlanta. (WSB/Cox Media Group)

Credit: WSB/Cox Media Group

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Credit: WSB/Cox Media Group

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