A man has died after an eel that was inserted into his rectum gnawed away at his bowels, causing agonising injuries which were eventually fatal.

The 59-year-old man, a chef, was reportedly taken to a Sichuan hospital complaining of abdominal pain, dehydration and a great deal of anal bleeding. He was soon diagnosed as being in a severe state of shock.

Doctors were mystified as to the cause, and obtained permission from his family to undertake an exploratory laparotomy. Cutting open his innards, they discovered a 50cm long Asian swamp eel lodged in his rectum.

Though dead, the eel had apparently already wrought havoc on his innards, biting its way through his intestines prior to dying. Internal bleeding and infection rapidly set in.

He was reported to have eaten a lot of eel the previous day, but otherwise doctors had no idea how the creature had got there. His condition quickly worsened.

He lingered for 10 days in intensive care but eventually succumbed to the injuries and sepsis.

The likely cause was eventually established – he had apparently been drinking with friends, and had passed out. His friends had decided it would be amusing to insert a live eel into his anus whilst he was comatose.

Police have reportedly begun an investigation.