A 26-year-old woman was sexually assaulted at a tube station platform, prompting an appeal from British Transport Police.
Police are looking to trace a man in connection to the incident at Elephant and Castle.
The victim was walking along the northbound Northern Line platform at Station at 12.30am on Tuesday March 28.
She passed a man sat at a bench who suddenly stood up, grabbed and sexually assaulted her, the police said.
Investigating officer, PC Louise Wilmot, said: “Understandably this was a very frightening experience for this woman – it was unexpected and highly inappropriate.
"We will not tolerate behaviour such as this and will always take firm action against perpetrators.
“I would like to hear from anyone who can help us identify this man.
"If you know who he is, please get in touch as your information will help us investigate.”
Anyone with information should either send a text message to British Transport Police on 61016 or call 0800 40 50 40 quoting reference 354 of 25/04/2017.
Alternatively, information can be passed on anonymously to independent charity Crimestoppers on 0800 555 111.
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