Detectives are appealing for the victim of an assault to come forward and speak with them.
At approximately 21:00hrs on Thursday, 11 July, witnesses saw a man on a Route 3 bus – travelling in the direction of Crystal Palace – who appeared to be bleeding.
The man got off the bus at Gipsy Hill where he told a member of the public that he had been stabbed and was heading to a friend’s house for help. He was last seen walking into the Salter's Hill entrance to Norwood Park.
Officers have carried out enquiries to trace the man but it appears that he has not sought medical treatment.
The man is described as white, aged between 30 and 40 years old and 5ft 7ins tall. He was wearing dark coloured jeans and a baseball cap.
Anyone with information regarding the victim is asked to contact detectives from the Central South Command Unit via 101 quoting reference Cad 9548/11July.