A man found unconscious in a Mitcham street with an unexplained head injury has died.

Derek Monger was found by residents in Lister Close last Thursday between 10.30pm and 10.45pm.

The 52-year-old from Mitcham died three days later in hospital. A postmortem examination gave the cause of death as a serious head injury.

Police say they are awaiting the results of further tests to establish how the injury was caused.

Officers say before he was found Mr Monger had been to the Railway Bell pub, London Road, Tooting.

He had been wearing jeans, trainers and a blue coat.

Police say they want to trace anyone who may have seen or spoken with Mr Monger between March 20 and March 22.

In particular Derek had told his family about a meeting with a motorist on either Tuesday, March 20, or Wednesday, March 21, who officers are keen to speak to.

Anyone with information should call Wimbledon CID on 020 8649 3039 or Crimestoppers on 0800 555 111.