A fire that was deliberately set in a carport near Whittier burned six cars and roared into an adjacent apartment building, damaging nine units and leaving nearly 30 people homeless, authorities said. The fire at 14300 E. Mullberry Drive, in an unincorporated area, burned for almost an hour until more than 40 firefighters brought the flames under control, said Ruben Sandoval, a Los Angeles County firefighter. Sheriff's investigators later determined that arson was the cause. No one was injured. "We've isolated the point of origin in an area of the carport near a car," said a deputy. Damage to the building and carport was put at $375,000. The fire caused another $175,000 damage to contents of the apartments and $80,000 damage to the cars, Firefighter Clarence Gardner said. The American Red Cross arranged for temporary shelter for those unable to return to their apartments.