The suspect exposed himself to two women after asking them for directions to the nearest toilets and started to perform a sex act.
Detectives have released CCTV of a man they wish to identify in connection with the incident which happened on December 6 last year, at 9.15pm.
The suspect asked two women in their 20s for directions to the nearest toilet which exposing him.
He started performing a sex act on himself, and the two women ran past him and contacted police.
Camden detectives are investigating and are appealing for witnesses and information.
They have released CCTV of a man walking along Black Path next to West Hampstead Railway Station.
The man is described as white, 5ft 11ins tall, with short dark hair. He was wearing an olive green hooded jacket, blue T-shirt, chino trousers and brown trainers with white soles.
Detective Constable Brett Jones, said: “I am appealing to anyone who thinks they recognise the man in the CCTV we have released to contact us.
“We believe a number of people would have been in the vicinity at the time of the offence. We are urgently seeking to speak to anyone who may have information in relation to this incident, or the identity of the assailant.”There has been no arrest at this stage and enquiries continue.
Any witnesses, anyone who has any information, or anyone who recognises the man in the CCTV is urged to contact the investigation team on 020 8345 0272 or via 101, or by tweeting @MetCC
To give information anonymously contact Crimestoppers on 0800 555 111 or visit crimestoppers-uk.org
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