OAKLAND -- A suspicious fire heavily damaged an East Oakland market early Tuesday, leaving in doubt when it might reopen, authorities said.

Firefighters responding to the In and Out Food Market, 8132 MacArthur Blvd., about 2:52 a.m. Tuesday found fires had started inside at two different areas, Batallion Chief Emon Usher said. "One did not start the other," he said.

That, and the fact that the market was "locked up tight" with security features such as a roll up door in place, was enough to deem it suspicious, Usher said. He said there was no sign of any forced entry.

It took 17 firefighters more than a half-hour to control the fire. No injuries were reported.

Officials said there was little damage to the cinder block structure itself, but that fire and heat inside caused more than $100,000 damage to food products and other areas.

Usher said it would be some time before the market could reopen.

Investigators have not been able to determine yet what caused the fires.

The market owner, whose name was not released, was contacted later by fire officials and told them the market had closed at its normal time of 5 p.m. on Monday. The market is insured, the owner told officials.