Detectives are keen to trace three men seen loitering in the area before a man was stabbed at a property in Roehampton.
The victim, believed to be in his late 30s, was found with serious injuries, following a break-in at the house, on Tuesday evening.
A 15-year-old boy has been remanded in custody after appearing in court today, charged with murder, and a 17-year-old male is being questioned by police.
Anyone with information should call police on 0208 721 4205 or Crimestoppers on 0800 555 111.
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