Thirteen spectators at a leading surfing contest in California have been hurt, some seriously, after big waves hit the seawall they were standing on.
Two 6m (20ft) walls of water crashed into the breakwater at Mavericks Beach, destroying scaffolding and sweeping dozens of people onto the rocks below.
The most serious injuries involved broken bones, emergency personnel said.
After the incident, one stretch of the beach was evacuated and the main viewing area was closed to newcomers.
Hundreds of people nevertheless remained to watch South African Chris Bertish win the $50,000 (£32,000) first prize.
'Came out of nowhere'
The Mavericks Surf Contest is the most lucrative big-wave contest in the world, but is only held when conditions are ideal, such as on Saturday. Some of the waves were reportedly 12m (40ft) high.
The Mavericks Surf Contest is the most lucrative big-wave contest in the world
California Department of Forestry and Fire Protection Battalion Chief Scott Jalbert said firefighters had been on the way to clear parts of the beach because of the potential danger for spectators, but had arrived too late.
He said a couple of hundred people had been on the seawall at the southern tip of Mavericks Beach, located about 25 miles (40km) south of San Francisco, when the waves struck.
"Nobody was swept away into the water. They were just swept onto the beach area pretty hard," he told the Associated Press. "It's pretty rocky."
"It's a force of nature that can't be predicted," he added.
An injured spectator, Pamela Massette, said the massive waves "just came out of nowhere and wiped us all out".
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