LOS ANGELES (AFP) - California's governor declared a state of emergency Friday after tsunami waves hit the US West Coast, forcing evacuations, damaging boats and leaving one man missing, swept out to sea.

   Governor Jerry Brown's declaration for four coastal counties unblocks federal funds to help clean up after waves triggered by Japan's devastating quake hit the US mainland, notably in northern California and Oregon.

   "The effects of the water surge continue to threaten the counties of Del Norte, Humboldt, San Mateo, and Santa Cruz," he said in a proclamation issued by his office.

   One of the worst hit towns was Crescent City, 560 kilometers (350 miles) north of San Francisco, where at least 35 boats were crushed and thrown on top of each other in a harbor. Some 7,000 people were evacuated before the tsunami struck.

   A tsunami in 2006 caused $25 million in damage to the town in Del Norte county, one of five in California where evacuation orders were issued, along with Humboldt, San Mateo, San Luis and Mendocino counties.

   "We have one of those harbors that sucks it in," said emergency services manager Cindy Henderson.

   A Coast Guard spokeswoman added that there had also been damage to about six boats in a marina in Santa Cruz, further south, after they collided with each other due to the buffeting tsunami waves.

   Santa Cruz port director Lisa Ekers estimated the damage at more than $10 million, according to CNN.

   Meanwhile a little away along the coast the US Coast Guard launched a search for a man swept away while attempting to take photos of the tsunami waves from the California shoreline.

   "A man was swept out to sea by a wave after he and two friends reportedly traveled to the shoreline to take photos of the incoming tsunami waves," the US Coast Guard said in a statement.

   "Two of the men were able to get back to shore and one is still unaccounted for," it added.

   Further north, in the state of Oregon, heavy damage was reported in the port of Brookings-Harbor where operations supervisor Chris Cantwell said 70 percent of the port's commercial basin was destroyed.

   "A third of our sports basin destroyed. We have boats on top of another.

Probably half a dozen sunk," he told The Oregonian newspaper.

   The waves hit the US West coast early in the morning local time, some 12 hours after the 8.9-magnitude earthquake struck off the coast of Japan, leaving more than 1,000 people feared dead.

   The US Coast Guard also announced that vessels were prohibited from transferring hazardous cargo until the seas had settled, adding that it "remains ready to respond to any reports of maritime emergency situations."