A heavy fire broke out in an El Cajon commercial building Monday night, collapsing the roof on about three-quarters of the building, according to Heartland Fire Department.
Firefighters received a call at 7:25 p.m. of flames spreading through the roof of a commercial building, prompting 27 fire units to respond to the incident.
Crews are currently trying to keep the fire from spreading and are trying to contain it to one portion where it is still actively burning.
First responders expect to be there for at least four to eight more hours, according to HFD.
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Nobody was inside the building at the time of the incident, no injuries were reported and no cause has been determined at this point, according to HFD Public Information Officer Andy McKellar.