Mystery after fishing captain and his girlfriend go missing while taking their boat out off Cape Cod

Shawn Arsenault, the boat’s captain, was going clamming with his girlfriend when their boat seemingly vanished.

An extensive search is underway after a fishing boat went missing off the coast of Cape Cod – and the ship’s GPS was discovered abandoned on the beach.

The Coast Guard has been searching for the F/V Seahorse, a white 30-foot fishing boat with a mermaid on the bow and “Seahorse” painted on the stern, since Sunday, WCVB reported.

The boat and its captain, Shawn Arsenault, were fishing near Eastham's Target Ship Wreck in Cape Cod Bay; however, a cellphone tracking placed the boat 2 miles offshore of Chatham, Massachusetts, about 15 miles away and along the coast.

Arsenault, 64, and his girlfriend had set sail out of Orleans, about halfway between Eastham and Chatham, with plans to go clamming.

Officials received reports that Arsenault was throwing items overboard just after leaving Orleans.

A search is underway after a fishing boat, its captain and his girlfriend went missing off the coast of Cape Cod over the weekend. (U.S. Coast Guard Sector Southeastern New England)

“It was reported he was throwing something overboard,” Coard Guard Commander Cliff Graham said. “I can’t confirm what kind of equipment or what it was specifically.”

Arsenault’s brother told the outlet his boat was just checked out by a mechanic ahead of the trip, and everything seemed up to par.

“The boat was just checked out by his mechanic, he said everything was A-OK. he just got a new radar, a fish finder, and he was all excited about that. He got it all hooked up. He said he was not coming home until he has his 30 bags,” the brother said.

On Sunday morning, Sam Miller and her dad were walking on the beach and found a GPS navigator saying “F/V Seahorse,” and left it along with a note on Arsenault’s truck. It’s unclear how they tied the boat to his specific truck.

“I noticed in the surf there was something floating, so I went down to see what it was, and it turned out to be a GPS unit off of a boat,” Miller said.

The next day, they discovered the note and truck remained untouched and called the harbormaster, who then alerted the Coast Guard.

As the investigation enters its fourth day, Arsenault’s brother said, “You’re in my prayers, brother. I hope God takes care of you.”

The Coast Guard is urging members of the public with any information to call the Sector Southeastern New England command center at (866) 819-9128.