The Canadian navy will be heading to the coast of British Columbia to investigate claims that a diver may have come across “the lost nuke” – a Mark IV bomb that went missing after an American B-36 bomber crashed in the region during the cold war.

Diver Sean Smyrichinsky was wrapping up a day of diving near Haida Gwaii, an archipelago 80km west of the coast of British Columbia, when he stumbled across what may be the remains of the world’s first known “broken arrow” – the code name for accidents involving American nuclear weapons.

“I was just looking for fish for the next day. I figured I would do a little reconnaissance dive looking around and on my dive I got pretty far from my boat,” he told the Canadian Broadcasting Corporation. “And then I found something that I had never, ever seen before.”

The object was huge, he said, measuring around 12 feet long. “It resembled a bagel cut in half, and then around the circle of the bagel these bolts all molded into it, like half spheres. It was the strangest thing I had ever seen.”

He came out of the water, excitedly describing the bowl-shaped object and its bolts that were bigger than basketballs. “I started telling my crew: ‘My God, I found a UFO.’” He sketched a rough outline of what he had seen on a napkin.

Read More: The Guardian