Flames broke out in Ben's Restaurant, 6601 Westminster Ave., early Wednesday, causing $150,000 in damage, a city fire official said.
Fifteen firefighters battled the blaze for 31 minutes before bringing it under control at 6:35 a.m., Westminister Fire Battalion Chief Hal Raphael said.
No one was injured in the fire, which Raphael said was of suspicious origin.
The preliminary investigation indicates that the fire was started in the kitchen to conceal a burglary, Raphael said. The fire was detected when the morning cook opened the back door to the kitchen at 6 a.m. and spotted the fire.