The Cosco Busan struck a tower of the Bay Bridge on Wednesday morning amid dense fog, creating a long slash along the ship that allowed bunker fuel to spill.

San Francisco Mayor Gavin Newsom criticized the Coast Guard for initially saying on Wednesday that just 140 gallons had spilled. He said the city would hold those responsible accountable, and threatened legal action if necessary.

Bud Leland, deputy director of California's Office of Spill Prevention and Response, told Reuters the spill was the worst in the San Francisco Bay since his office came into existence in 1991. He said it would likely take several weeks to complete the cleanup.

Tides carried the bunker fuel into the Pacific Ocean beyond the Golden Gate Bridge and people near the spill on Wednesday reported headaches and nausea. The spill reached the famed former prison island of Alcatraz and as far north as Marin County.

HUNDREDS AT WORK CLEANING

The Coast Guard said 200 people were working on the cleanup and had recovered about 9,500 gallons of the oil. Yet the pace of cleanup slowed as tides spread the fuel over a larger area.

Eleven oil-skimming boats were in and around the bay and workers spread booms across long sections of beach and water near San Francisco, a city bound by water on three sides.

Steve Edinger, assistant chief of the California Department of Fish, said workers had found six dead birds and 26 others alive slicked with oil.

The Cosco Busan, owned by Greek firm Synergy Maritime and chartered to South Korea's Hanjin Group [HANJ.UL], left the Port of Oakland early on Wednesday and hit a fender around a support tower of the Bay Bridge on an especially foggy morning.

Only the fender was damaged on what is a vital transportation link between San Francisco and Oakland and Berkeley in the East Bay.