SOUTH SAN FRANCISCO (CBS SF) — Two boats blown off their moorings by high winds crashed onto the rocks near Oyster Point Marina in South San Francisco Wednesday morning.

The Coast Guard received a report around 7 a.m. that a boat had broken free from its moorings and crashed into the rocks near the marina at 95 Harbormaster Road.

A view from KPIX Chopper 5 showed it was one of two sailboats that had broken free in the channel. The waterway also had debris that had been blown from an unknown source.

No one was aboard at least one of the vessels at the time and the crashes did not cause any pollution, according to the Coast Guard.

San Mateo County Harbor District harbormaster Scott Grindy said the boats had been anchored for months in the waters under the jurisdiction of the city of South San Francisco.

Grindy said the city was waiting for 30 days or more of non-use of one of the boats so they could seize it, but people were spotted periodically on board.

The boats broke free likely due to “really bad wind last night,” Grindy said.

The Coast Guard said the boat’s owners will be responsible for hiring a salvage company to remove the vessels from the rocks.

Wednesday’s high winds and choppy bay waters also forced the National Parks Service to close Alcatraz Island to tourists.

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