A group of snorkelers were diving near the Ningaloo Reef in Australia when they were approached by a giant manta ray that started flipping over in the water, signalling to them that it had a problem - a fish hook was embedded under its eye.
One of the divers made several attempts to remove the hook, while the other filmed the whole operation to upload the footage to his social media account afterwards.
"It was an extraordinary half hour or so, and such a clear illustration that these animals have intelligence, trust, and a strong association with folks who treat them with respect," the diver wrote.
Manta rays are large rays that can grow up to 7 metres in width. Unlike stingrays, they pose no threat to humans.