Officers investigating the rape of a woman in the park at Dickens Square are appealing for a possible witness to come forward.
The attack was reported to have happened in the early hours of Saturday 20 July.
It is being investigated by officers who are appealing for information about a man who assisted the victim to safety.
The victim, aged in her twenties, was walking in the area of Great Dover Street at around 2.15pm when she was grabbed around the neck from behind, threatened, and taken by an unknown man to the nearby wooded track – known as Butterfly Walk – leading from Brockham Street to Dickens Square.
She was then raped a number of times.
During the attack, the woman managed to break free and ran a short distance to Trinity Church Square. The suspect caught up with the victim, at which point a car stopped. The suspect exchanged some words with this driver, who then left. Officers do not have a description of this car or driver.
Almost immediately afterwards, either the same car or a different car stopped and the victim managed to escape to the safety of the vehicle whilst the suspect walked off.
The driver of this car, who is thought to have been a black male in his early twenties, and possibly driving a seven seater vehicle, then drove the victim to Walworth Police Station.
Detective Sergeant Jonny Norman from Central South's Safeguarding team is leading the investigation.
He said: "We are very keen to trace the driver of the vehicle who drove the victim to Walworth police station.
"Did you drive a distressed women to Walworth Police Station, in the small hours of Saturday 20 July? We would like to speak to you to support our ongoing investigation.
"We would also like to speak to the first driver who originally stopped, although unfortunately we do not have a description of this person.
"We are treating both of these individuals as possible witnesses and we would like to highlight that you are not in trouble."
Officers are also linking this incident to a separate sexual assault on another woman, aged in her twenties, reported to have happened a short time afterwards, at around 3.50am in Borough High Street.
In this incident, the suspect grabbed hold of the woman, led her down a nearby street, but then left the scene. She was physically unharmed.
Anyone with information that could assist the investigation and has information about either incident, is urged to contact police via 101, or by tweeting @MetCC quoting CAD reference CAD 6111/02Aug19.
A 28-year-old man has been charged in connection with offences against both women and will appear in court at a date in late August.
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