The victim, who is in her mid-teens, was attacked near the playground and exercise equipment in Ducketts Common Park.
Police want to speak to two young men in connection with the investigation.
The first is described as black, of large build, aged about 18 years with an Afro hair style. He was wearing a black coat which zipped up to his chin, dark trousers and black trainers.
He may have been carrying a small black Nike bag.
The second man is described as black, also of a large build and aged about 18 years.
He was wearing a “Puffa style” coat, possibly with a Nike logo on the front, dark trousers and a dark hat that had a circular logo with a cross through it.
He also wore a hoodie, and over his face had a black motorbike-style scarf with white stitching.
The incident took place at around 9pm on March 12,
- Anyone with information is asked to contact detectives on 020 8217 7448 or 07342 080948. You can also contact Crimestoppers on 0800 555 111 if you do not wish to give your name.
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