Knoxville (WVLT) - It's definitely been a long day for Knoxville's firefighters.

For the latest on when they may be going home, is at the Media Staging Area on Depot and gathering the latest information.

Jackson Avenue is closed. It will remain closed as firefighters continue to water down the building.

They're trying to bring the heat down, and protect a third building from catching fire.

Early Wednesday morning, the Knox County Sheriff's Department flew over the scene with their chopper, gathering video for their records.

Crews have been on scene all night, and all day, keeping a close eye on this building.

They have to make sure it's safe, before they can start to look for a cause.

"Most likely, they'll bring in some front end loaders and start digging those bricks out to look for the hot spots, and will put them out individually," says Knoxville Fire Captain Darrell Whitaker.

Inspectors will go in after the fire is completely out, and there's no chance of a rekindle.

That might not happen until Thursday.

Read More About the Fire: