This is the heartbreaking moment a 13ft-long giant marlin fish was found dead, drifting near a beach in Thailand.

Muhammad Bisanoon, 35, was about to sail on his boat when he noticed the huge silver fish in the water in Satun province on December 17.

The fisherman paddled near the animal to check on it as he thought it was struggling to swim.

However, when he pulled up near the huge creature to help it, he found it was already dead.

He said: "I've never seen a Marlin fish this big since it is usually found in the deep water. I am confused how it could have died."

Muhammad believed it must have died even before it was pushed by currents near the beach while it was laying eggs nearby.

He tied a rope around its body before taking the fish into his boat and carried it back to land.

Five men had to carry the fish as it weighed 440lbs (200 kgs) and estimated it was at least 20-years-old.

They reported the sighting to the local marine centre whose staff arrived to take it back to the facility to investigate the cause of death.

Sea fishing expert Tassapol Krajangdara said the creature may have died due to strong monsoon winds which blown it off course near the coast.

A marlin has an elongated body, a spear-like snout used for hunting food, and a long, rigid dorsal fin which extends forward to form a crest.