OCEANSIDE -- A fire Saturday morning did about $300,000 damage to a single-story house, Oceanside Fire Department officials said.

About 1:20 a.m., fire crews from Oceanside and Vista arrived at 4237 Diamond Circle to find a heavy blaze in an unoccupied house, Battalion Chief Bob Cotton said. It took the crews about 30 minutes to bring the fire under control, he said.

One firefighter was taken to Tri-City Medical Center, treated for unspecified injuries and released, Cotton said.

The fire's cause is under investigation.