The large fire at a construction site that shut down Kingston Pike in West Knoxville on Thursday was an accident.

Construction crews building the future Southeast Bank first saw flames in a breezeway between the two main structures, where a combustible fire heater was operating. The Knoxville Fire Department believes that is what started the fire, which quickly spread.

All of the workers were able to escape without injury. The remains of the building were demolished on Friday morning.

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A large fire at a bank construction site in Bearden shut down Kingston Pike on Thursday afternoon. 

It happened at the under construction Southeast Bank building on Kingston Pike near Homberg Drive.  

The blaze sent flames and smoke high into the sky and even tossed roofing material from the under construction bank across the street, Knoxville Fire Department spokesperson D.J. Corcoran explained. 

All 12 of the construction site workers escaped after one of them noticed the flames and yelled "fire," Cpt. Corcoran added.  

There were no reported injuries and it took firefighters about 10 minutes to control the flames.

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Crews contained the fire to just the one building.

Corcoran said there were small explosions. Authorities said the small explosions could have been caused by propane tanks or windows popping. The fire threw some of the building's roof material across the street.

Arson investigators are on the scene Thursday afternoon to try to determine the cause of the fire.

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