A spokeswoman said on Sunday that the arm is thought to have belonged to a man due to its hairiness.

Fishermen found it washed up on the Rhine bank on Friday and called the police.

She said forensic scientists have suggested the limb was in the water for about a week. Attempts will be made over the next couple of days to secure fingerprints and DNA samples from it.

Missing persons files are already being examined, while detectives say all possibilities remain open, from an accident, through suicide to murder.