A Tempe sports bar popular for its karaoke and team trivia nights caught fire Sunday morning and firefighters work to extinguish the blaze.

Reports emerged around 7:30 a.m. that heavy smoke was billowing from Doc and Eddy's on Rural and Baseline Roads. The bar's sign and storefront were blackened as firefighters sprayed water on the roof.

Andrea Glass, the interim assistant chief with the department's community risk reduction unit, told The Arizona Republic that fire crews had extinguished most of the the blaze by 8:30 a.m. and were putting out smaller fires around the area.

Charlotte and Patrick Karnos have owned Doc and Eddy’s for more than 30 years.

Charlotte Karnos said the fire started early this morning in the bar’s office.

"It was a cigarette in a trash can, from what I understand," she said."Staff was closing when it started. They tried to put it out … but it got in the attic."

She said the fire spread quickly throughout the building. Several hours after it started Tempe and Mesa fire fighters were still trying to put out flames in the kitchen area, spraying water down into the attic from above.

"It's gone. It's a total loss," Karnos said.

But she said customers shouldn't worry.

"Absolutely we'll rebuild," she said. "We have good insurance."

Glass said the restaurant lacked a sprinkler system because of when it was built and she believed the damage would have been less severe had sprinklers been installed. Though the building suffered major damage, there were no reported injuries, Glass said.

The cause of the fire remains under investigation.

This is a developing story. Check back with azcentral.com for updates.