Plastic pollution was found inside a dead green sea turtle that washed on a popular Thai island.

The marine creature had a bloodied mouth and back passage when it was discovered by a fisherman in front of a tourist hotel visiting Koh Samui on January 3.

Animal rescuers believed that the seven-year-old turtle weighing 10kg had gastric indigestion after consuming plastic waste as a strand of plastic bag protruded from its mouth.

The turtle was buried in the sand near the beach before it was taken by veterinary staff from the Center for Marine Resources Research and Development to check again.

The fisherman who found the creature said: 'The turtle may have thought that the plastic bags were jellyfish and was attracted to eat them. So please don't throw trash in the ocean.

'I will urge tourists to properly dispose of their plastic waste to prevent similar incidents from happening in the future.'

The green sea turtle was listed by the nongovernment organisation International Union for Conservation of Nature (IUCN) as endangered.

Research from the World Wildlife Organisation suggests that 52 per cent of the world's turtles have eaten plastic waste as floating plastic bag can look like a lot of jellyfish, algae, or other species that make up a large component of the sea turtles' diets.