A woman was "viciously" attacked in an unprovoked assault in a Hounslow park.
The 33-year-old female was alone in Lampton Park when she was set on by an Asian man before a member of the public intervened and the suspect fled.
Police in Hounslow are keen to speak to the person who came to the aid of the woman.
Officers are also appealing to any witnesses to the attack or anyone else who may have any information that can assist with the investigation.
The suspect is believed to be aged between 30 and 40 and around 5ft 11ins tall and of slim build.
At the time of the offence he was dressed in all black including a T-shirt with white writing on it.
The incident happened on the night of Thursday July 13 with police describing the attack as "unprovoked, vicious and sustained".
If you have any information in relation to this attack contact Detective Constable Hayley Whisker at Hounslow.
Alternatively call Crimestoppers anonymously on 0800 555 111 or tweet @MetCC.
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