A man in China was severely injured when he fell into a tank of eels and one of the slippery creatures squeezed up his bottom.

Li Chang, a fishmonger in Guangzhou, was perched on the edge of a tank full of eels when he suddenly slipped in, reports The Sun.

The eels, which were waiting to be cooked, began writhing around when they were disturbed by the 43-year-old.

"I guess they were scared when I suddenly landed in the tank so they started wriggling everywhere," Chang said.

"Several shot up my trouser leg. And then, to my horror, I felt one go up my bottom."

Too embarrassed speak up about his ordeal, Chang continued working.

"I didn't say anything at first when I climbed out ? I was too embarrassed. I dried myself off and tried to carry on working, but it was just too painful."

The pain soon became too much for the fishmonger, whose subsequent collapse prompted his colleagues to call an ambulance.

Doctors operated for five hours to remove the eel and tend to Chang's severe internal injuries.

"The eel had badly injured the patient. If he had not arrived when he did he would have died. We expect he will make a full recovery though," a hospital spokesperson revealed.

"The eel was as wide as two fingers and as long as a man's arm."