Police are appealing for help tracing friends and family of a man with a distinctive dragon-like tattoo after he was rescued from the Thames.

The identity of the man, who is in a critical but stable condition, remains a mystery after he was pulled from the river near London’s Putney Embankment, Scotland Yard said on Saturday.

Detectives have ruled out foul play and believe the man, thought to be in his 30s, injured himself after entering a section of the river he thought was shallow on July 26.

“He was not carrying any identification and due to his poor state of health police are keen to trace his family as soon as possible,” the Metropolitan Police said.

The man was wearing a camouflage T-shirt with “Now or never, no regrets, past/present/future” written on it.

“He has two distinctive tattoos on his left hand and one on his lower right leg, that are faded black in colour,” a statement added.