The incident occurred in the Union Street area of the town at around 2.25am on Sunday 15 September 2013.
Union Steet is the one-way road from the rear of Debenhams, past Jubilee multi-storey car park, to the Kings Road.
A local 17-year-old youth has been arrested in connection with the incident, however officers still need witnesses to come forward and help with the investigation.
In particular, the police would like to trace a white man, with a stocky build, who was wearing a long-sleeved white top, and dark trousers. He was in the area at the time of the incident and may have information vital to the investigation.
It is also believed that a number of other people were in the area at the time who may also have information which can assist officers with their enquiries.
It was a busy time in Harrogate on Saturday night into Sunday morning when the night time economy is at its peak.
Anyone who can help the investigation is urged to contact North Yorkshire Police on 101 – select option 2 – and ask for Harrogate Protecting Vulnerable Persons Unit.
or email firstname.lastname@example.org
If you prefer not to give your name, Crimestoppers can be contacted on 0800 555 111.
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