POLICE are appealing for help in discovering what happened to an elderly man found lying in the street with serious head injuries.

The 77-year-old was discovered at around 8.40am last Thursday lying on the ground between Hibernia Point and Duxford House in Wolvercote Road, Thamesmead.

He was taken to a south London hospital, where he remains in a critical condition.

Bexley police are keeping an open mind about what happened.

Investigating officer Detective Sergeant Martin Roe said: "We are investigating the circumstances of his unexplained injuries and are appealing to the public who may have been in the area between 8.20am and 8.40am."

He said the area was on the route to schools.

People passing on foot or in cars may have seen what happened.

Police have leafleted residents in the area and stopped traffic to question motorists.

The injured man is 5ft 8in tall with receding short grey hair.

He was wearing a black three-quarter-length padded jacket, grey trousers and black shoes.

Anyone with information should call Det Sgt Roe on 020 8284 9122 or Crimestoppers on 0800 555111.