China’s Loch Ness monster has been sighted. Or so Chinese state-run television says. Not just one, but more than a dozen huge creatures can be seen churning across Lake Kanasi in remote western China, leaving a foamy wake more like an enormous motorboat than a big fish.

A rare video filmed by a tourist at the lake in the Heavenly Mountains of the wild Xinjiang region, has reignited debate over the existence of an underwater creature that can compete with the Loch Ness monster in both mass and mystery.

The grainy film shows about 15 objects moving at high speed just beneath the surface of the lake and whipping the smooth blue water into a bubbling white frenzy. Chinese Central Television broadcast the video on its news channel, describing the footage shot by a passing tourist on July 5 as the clearest ever seen of a legendary beast that has been rumoured for centuries to live in the depths of Lake Kanasi.

Local myth among the Chinese Mongolians living in the scenic mountains near the Russian and Mongolian borders has it that the animals have been known to drag sheep, cows and even horses from the shore and into the deep to devour them.

Yuan Guoying, of the Xinjiang Institute of Environmental Protection, told The Times that the video provided important proof in his more than two decades of research at the lake. “Only fish could make waves in this formation. I think the video is real.”

The television commentator described the sighting as the first since June 7, 2005 when two black creatures measuring more than 10 metres in length appeared on the surface swimming at speed from the shore to the centre of the lake. The newsreader described the latest appearance: “They sometimes gathered in a flock, sometimes spread about or moved shoulder to shoulder. The scene is grand and they looked like a fleet.”

State television made no attempt to identify the animals, saying only: ‘This time a large number of unidentified creatures emerged, bringing more mystery to Lake Kanasi.”

Professor Yuan has been on their trail since 1980 and has been gripped by the mystery since his first sighting in 1985 when he says he saw as many as 50 of what he called fish. “They looked like reddish-brown tadpoles because I could only see their heads on the surface. They opened their mouths to breathe and their length was about 10 to 15 metres.”

He spotted the animals again on May 28, 2004 when he was standing looking down at the lake from a nearby hill. “I thought there was a huge piece of black plastic in the lake and that someone had been polluting it. But then I released that it must be the back of a giant fish. I was shocked because they were just too big. Looking at them was like looking at submarines.”

When Mr Yuan got back to his office he tried to calculate the size of the animals by setting their proportions against those of the surrounding landmarks such as trees or the shape of the shoreline. “I didn’t dare say they were bigger than 20 metres because no one would believe me.”

Chinese researchers in the 1980s said the ‘monster’ was likely to be a huge member of the salmon family – one of eight species of fish living in the lake. Mr Yuan gave their name as Hucho Taimen, a freshwater salmon tht thrives in deep frigid waters. He says the biggest Hucho Taimen salmon ever captured was 2.1 metres long and was found in Russia.

The animals that roam Lake Kanasi live in an area about 24 kilometres by two kilometers and with an average depth of 122 metres and as deep as 188 metres at one point.

Mr Yuan believes that a lot more research is needed although China lacks the scientific equipment to make further studies. And it would be impossible to catch a fish of this size. “This fish will have tremendous strength.”

Other Chinese scientists have cast doubt on his findings, but Mr Yuan is adamant. “People will just say ‘You’ve got to be kidding’. But I saw them with my own eyes. I am a scientist. I have no choice but to believe what I saw.”

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