Man who survived being trapped at bottom of ocean for 60 hours opened up about the one chilling noise he heard

A man who survived 60 hours trapped underwater in an air pocket spoke about hearing a chilling noise during his ordeal.

On 26 May, 2013, a tugboat was struck by a wave and flipped it upside down with 12 people on board. One of those was Harrison Okene who was working as the ship's cook and had been in the toilet when the vessel capsized.

His world had turned upside down, the toilet struck him on the head and then the lights all went off with the vessel sinking to the seabed about 30 metres below the surface of the water.

The boat, the Jascon-4, had sunk about 20 miles off the coast of Nigeria, and the interior was starting to fill with water while Harrison couldn't see what was going on properly.

He found some of his crewmates struggling with a hatch in an attempt to escape but the then-29-year-old cook made a decision which seemed illogical yet ended up saving his life and swam further inside the sunken ship.

Harrison Okene survived for 60 hours in an air pocket after his boat was hit by a wave. (YouTube/DCN Diving)

Harrison knew there would be air pockets within the boat where he might be able to survive for a while and as he swam he was swept into another toilet, with the door shutting behind him but the room not completely filling with water.

Trapped in the darkness, he heard the terrible sound of his crewmates 'calling and crying', telling The Guardian that he heard 'so many shouts, shouts, shouts'.

He broke the door handle trying to open it and get out again, but was able to prise it open and find a lifejacket and torch, and remembered that 'one after another' his crewmates fell silent which he at first thought had meant they escaped.

Harrison was able to make a rope out of overalls so he could find his way back to the air pocket in the darkness, and found some food and drink.

He also fashioned a raft to try and stay out of the cold water as he realised he wouldn't be able to open the hatch and he could only sit tight.

He could hear his crewmates at first, then they went quiet. He initially thought they'd escaped, but Harrison was the only survivor. (YouTube/DCN Diving)

For 60 hours he was stuck down in the air pocket, still able to hear vessels moving in the water above him, and could feel crayfish eating away at his body as he waited.

He heard another sound closer to him which turned out to be a diver placing a buoy on the boat to warn other ships where it was, and afterwards he saw a little bit of light.

On his first trip diving back into the water he couldn't find it but on the second go he spotted a diver, with bodycam footage from them showing a pale, floating hand which was originally mistaken as dead.

The diver thought he'd found a body but then the hand grabbed him, with Harrison rescued from the wreckage and taken to a recompression chamber.

He was the only survivor of the disaster, when Harrison could no longer hear his crewmates he thought it meant they had escaped but they had instead drowned.

Despite his ordeal at sea, Harrison ended up retraining as a diver, saying in 2015: "I have faced a lot of my fears in my life, and I decided to face this once and for all."