The legend of the Kraken, a giant cephalopod from Greek and Norse mythology that attacked ships and dragged sailors to their doom, is many hundreds of years old. Here is an unlikely, but apparently true, story of the US Navy frigate USS Stein, whose sonar dome was probably attacked by a colossal squid in 1978.

USS Stein was underway when her anti-submarine sonar gear suddenly stopped working. On returning to port and putting the ship in a drydock, engineers observed many deep scratches in the rubber “NOFOUL” coating of the sonar dome. In some areas, the coating was described as being shredded, with rips up to four feet long. Large claws were left embedded at the bottom of most of the scratches.

The IFLScience blog notes that in an effort to understand the “Stein Monster”, Navy biologist F.G Wood was called to inspect the NOFOUL coating. He noted that the teeth, or claws, found on the dome were the likely culprits of the large tears, demonstrating that they perfectly matched the width of each.

He concluded it was a massive squid, owing to the structures of the teeth, but didn’t rule out something that hasn’t yet been found in the ocean. The only snag is that it has widely been reported that a squid with teeth like this would have to be in the region of 45 meters (150 feet) long, making it around half the length of the Statue of Liberty.

The claws embedded in the coating appear to belong to a colossal squid, which differs from its giant squid relative by overall body mass and large hooks that line the tentacles. Colossal squid are thought to have a total length of 10–14 meters (33–46 ft).

Here is a short segment from a documentary, Arthur C Clarke’s “Mysterious World,” showing the damage to the sonar coating and a claw from a supposed squid species that may have attacked the radar dome of the USS Stein.

USS Stein: The Ship Attacked by a Monster Squid. Original Documentary Footage