A 17-year-old girl has been threatened with a knife and raped in Thamesmead during a "terrifying" attack, police say.

The girl waas walking along Binsey Walk on Tuesday (December 9) at around 7.33pm when she was approached from behind by a man who threatened her with a knife and dragged her to a bin area under a nearby walkway.

After raping her, the man ran off along Binsey Walk towards Harrow Manor Way.

He is described as black, of average build, approximately 5ft 8in tall and around 25 years old.

Police say he was wearing dark blue jeans, black Addidas trainers and a dark coat,  described as bulky with a hood.

His face was partially covered by a black scarf which may have had grey stripes. He was also carrying a black bag.

The victim described him as speaking with a London accent and thought he possibly was of African descent due to a number of phrases he used and some of his mannerisms.

Detective Inspector Neal Burton from the Met's  Sexual Offences, Exploitation and Child Abuse Command said: "This was a terrifying experience for the victim who has been extremely brave in coming forward to report the rape and assisting the investigation team, who are following every available investigative lead to identify and arrest her attacker as soon as possible."

Anyone who saw something should call police on 020 8721 4677 or Crimestoppers on 0800 555 111.