A rare sea creature washed up on Redcar beach in the U.K. over the weekend, leaving beachgoers baffled over its identity. However, it was later revealed the marine animal was an Ocean Sunfish.

It was not clear when the creature washed ashore, but by the time people saw it, the Ocean Sunfish had already died.

After several beach walkers posted pictures of the Ocean Sunfish on social media, many users expressed their sadness and shock over the discovery, Gazette Live reported. Some people claimed the creature had likely died after drifting through currents from the tropics into the cold waters.

Ocean Sunfish, which are considered the largest bony fish in the world, are normally found in moderate or tropical waters. These creatures can grow around 10-foot-long. The size of the Ocean Sunfish that washed up on the shore was not revealed.

According to the National Geographic, Ocean Sunfish are vulnerable due to their decreasing population in the wild.

"The Sunfish develops its truncated, bullet-like shape because the back fin which they are born with simply never grows," the report on National Geographic stated. "Instead, it folds into itself as the enormous creature matures, creating a rounded rudder called a clavus."

Ocean Sunfish are also known with their modern scientific name Mola, coined by Swedish naturalist Carl Linnaeus in the 1700s. Mola in Latin means "millstone" and describes the ocean sunfish’s somewhat circular shape.

Mola are frequently seen basking in the sun near the surface. In several instances, many people have mistaken these creatures for sharks when their huge dorsal fins emerge above the water, the National Geographic report said.

This is not the first time a mysterious and bizarre-looking creature has washed up on a shore, and left experts and beachgoers baffled over its identity. However, in most cases, these creatures are identified after their photos or videos surface online.

Earlier this month, police officers patrolling the beaches of a British town spotted a massive sea creature that washed up on the shore. The creature's size shocked the officers.

The police department posted a photo of the enormous creature on Twitter, identifying it as a conger eel.

"Me and my crewmate were about to break out doing the conga, with this rather impressive conga washed up on Exmouth beach this morning," a spokesperson wrote at the time.

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