The building, at 2941 N Hesperian St B, in Santa Ana, caught fire at around 2:25 a.m. in the area of Bristol and Hesperian streets.
A Sherwin-Williams paint store located next to Discount Movers was spared from the flames due to a firewall separation between the two businesses.
73 firefighters from OCFA, Anaheim, Orange, Garden Grove fought the flames from outside the building, finally knocking down the fire at around 4:15 a.m., according to the OCFA. Then the firefighters had to go inside the building to look for hot spots.
The Bristol Street off-ramp from the eastbound 22 Freeway was blocked off during the fire.
The cause of the fire is not yet known.