Detectives are investigating after a sexual assault was reported in the early hours of Tuesday morning (June 20).
A spokesman from Metropolitan Police said: "A 21-year-old woman was assaulted at approximately 2.25am in the Springfield Gardens area of Acton.
"Detectives from the Met's Sexual Offences Exploitation and Child Abuse Command are investigating."
At this stage, no arrests have been made, and enquiries into the incident continue.
Police are urging anyone with information, or who heard anything suspicious, to contact them on 101.
Those wishing to pass on information can also do so anonymously, by contacting Crimestoppers on 0800 555 111.
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