The blaze, which has burned about 200 acres, was reported at 7:23 p.m. on the Brisbane side of San Bruno Mountain but quickly spread over the top of the mountain to the South San Francisco side, North County Fire Authority spokesman Clyde Preston said.

Residents on Kings Road, Trinity Road, Margaret Avenue and Paul Avenue in Brisbane were ordered to evacuate, according to Preston.

About 200 firefighters are battling the blaze, which is not at all contained, Preston said. Two helicopters used to battle the flames when the fire first started had to be grounded after the sun set, according to Preston.

"The whole hill is glowing with fire," Preston said. "We're setting some ground fires to try to force the fire back onto itself ... and to burn back up the hill away from the houses."

South San Francisco resident Patty Nelson said she could see the fire burning "a whole top" of the mountain from her back porch and the flames had "outlined" the mountain.

"It's very visible," Nelson said. "A fire that big is frightening. You can smell smoke."

San Francisco International Airport officials said flights to and from the airport tonight have not been affected due to the fire.

(clo)