Police have launched a murder investigation after a man was seen trying to dump a body in the River Thames.
Officers responded to a call just before 3am on Friday morning concerning the incident at Deptford Wharf.
The man was later stopped in his car on Evelyn Street, about half a mile back from the water. The body of a man in his 20s, who had suffered head injuries, was found in the vehicle.
The driver, in his 50s, was arrested on suspicion of murder and taken into custody at a police station in south London.
Officers believe the victim was killed at an address in Thornton Heath in Croydon. A woman was also arrested at an address in Thornton Heath on Friday morning.
Detectives are not looking for anyone else in connection with the incident.
Police are asking any witnesses or anyone with information to call the incident room at Sutton on 020 8721 4005 or Crimestoppers anonymously on 0800 555 111 or via Crimestoppers-uk.org.