A man has been arrested on suspicion of sexual assault after a reported attack in the early hours of Tuesday morning.
Police said they were called to Cotham Street, near Walworth Road, at 12.26am on Tuesday, August 6, after reports of a sexual assault.
They found a woman in her 20s who told them she was attacked by a stranger who had the fled the scene.
Officers tracked down a suspect who in the vicinity and arrested him on suspicion of sexual assault.
He is now being questioned in a south London police station.
The woman, who did not require hospital treatment, continues to be supported by specialist officers during the investigation.