California wildfire partially contained

SAN FRANCISCO, Oct. 13 (UPI) -- A wildfire on San Francisco Bay's Angel Island, fueled by thick vegetation, was 20 percent contained Monday morning, fire officials say.

Fire officials said since the wildfire began on the island state park Sunday night, it had consumed 250 acres, about a third of the isle, the San Francisco Chronicle reported.

Marin County Fire Battalion Chief Mike Giannini said Sunday the wildfire grew in size to a point that it could be seen in nearby San Francisco and its maritime location was hindering containment efforts, the newspaper said.

"We are dealing with some real heavy vegetation and some very active flames kicking up," Giannini said. "It is challenging not only because of the heavy vegetation but in getting crews up there."

Helicopters were aiding the containment efforts as investigators prepared to learn what caused the fire, the Chronicle reported.

"The investigation has not gotten fully under way yet," Giannini said. "Now that we have some first light on the fire, we'll be able to get out there and look for clues that will help determine the cause."