A Thai fisherman was horrified after he spotted a mysterious alien-like sea creature among the fish he pulled out of the sea. The creature had 20 long legs and was black in color.

Desha Srichai, 41, was fishing in Krabi province in southern Thailand on Nov. 30 when he came across the creepy-looking sea animal. According to Eminetra news, the fisherman poked the creature with a stick and freaked out when it started moving. He initially planned to burn it, but then decided to take some pictures and video of the sea creature.

Srichai shared the photo of the mysterious sea animal on social media in the hopes that someone would identify it. He then released it back into the sea.

"At first I thought it was just a twig but then the thing started to move. I was scared and leapt back," he reportedly said. "It confused me because that was the first time I'd seen such a strange creature."

Srichai shared the images with his friends, who told him it was most likely a dark black feather star.

"I used the stick to knock it back into the water. I hope I don't catch anything like that again."

Feather stars are marine animal with several feeding arms, and are found widely throughout tropical and warm-temperate waters, according to the Encyclopedia. They feed on planktons and are part of the crinoids, a group of marine animals that includes starfish, sea urchins and sea cucumbers.

There have been several instances in the past where mysterious creatures have washed up on shores. While experts have been able to identify many of the creatures, others have left them baffled.

Last month, a tongue-shaped sea creature washed up on the shores of a beach in Australia. A woman staying at Tangalooma Resort, on Queensland's Moreton Island, came across the creature while walking on the beach.

The woman took several photos of the bloated fish-like creature and sent it to the Queensland Museum for identification. Experts at the museums later confirmed the creature was an Obese Sea Pen (Cavernularia obesa).

Other common names for the animal include fat sea pen, hair sea pen, obese sea finger, octocoral, sea cactus, sea feather, sea finger and sea quill.

Beach
This is a representational image of a beach. AFP / Angelos Tzortzinis