San Diego Fire-Rescue Department investigators are working to determine what sparked a fire that burned an abandoned building at Liberty Station.
The fire was reported just after 8:30 p.m. Wednesday at a structure in the 2400 block of Cushing Road, according to SDFD officials.
More than 70 firefighters worked for several hours to put the fire out.
At one point, flames caused most of the building to collapse.
No injuries were reported and the cause of the blaze is unknown.
