The woman killed by a hit-and-run driver in Abbey Wood yesterday was apparently mown down while trying to protect an elderly male companion.
The victim in her 60s was pronounced dead at the scene after being struck by a black Ranger Rover in Finchale Road at the roundabout with Eynsham Drive at around 11am.
The male driver fled on foot and is still at large having mounted the pavement and killed the pedestrian in the 4X4.
He apparently lost control while attempting to cross the roundabout before careering over the kerb.
The car did not have number plates on it which appears to back up rumours it had been stolen.
Detective Sergeant Richard Budd said: "I am keen to hear from anyone who may have witnessed this tragic accident.
"It appears the victim had been walking with an elderly gentlemen and that she may have tried to prevent him being hit but was knocked down in the process.
"The gentlemen did not sustain any injuries and did not require hospital treatment.
"I am also keen to hear from anyone who may have any information or knows the man we are seeking to trace.
"Please do not stay silent as any information you provide will be treated in the strictest of confidence."
Formal identification of the victim's body has not yet taken place.
A post-mortem will be held on Monday at Greenwich Mortuary.
Anyone with any information is asked to call the Serious Collision Investigation Unit on 0208 285 1574 or Crimestoppers on 0800 555 111.
Did you see what happened or do you know the victim? Call 01689 885702.