CAPE ELIZABETH, Maine (AP) — A crew member fell asleep with a 55-foot trawler operating on autopilot before it crashed onto rocks on the Maine coast last weekend, the fishing vessel’s owner said.

The four crew members aboard the Tara Lynn II were rescued. But the vessel was pummeled during a storm, as winds gusted to 50 mph (80 kph) and 6-foot (2-meter) waves crashed ashore.

“Operator error is the cause of this accident,” David Osier, owner of the Tara Lynn II and Osier’s Seafood in South Bristol, told Maine Public.

The captain reported that the bridge alarm, which is intended to wake the crew at certain intervals, wasn’t activated as the autopilot navigated the vessel into shallow water early Saturday, Osier said.

Crew members issued a mayday call at 12:30 a.m., and the Cape Elizabeth Fire and Rescue Department’s Water Extrication Team used an inflatable boat to rescue the crew.

Damage was minor when the vessel ran aground, but it was pounded by waves after it came to a rest on rocks, leaving the owner and insurance company no choice but to demolish it. On Friday, Determination Marine, a salvage company, was overseeing the dismantling of the fishing vessel with excavators, a process that could take several days.

The Associated Press could not reach Osier on Friday. He was at the site watching the demolition of the vessel, and was unavailable, according to someone who answered the phone at his business.