A woman was assaulted in the centre of Cirencester in the early hours of Sunday morning.
The incident took place near to the alley between Brewery Court and Ashcroft Road between 3am and 3.15am.
The victim managed to fight off the male who was seen running off towards Cricklade Street empty handed.
Gloucestershire police have asked local businesses and residents in the area to check their CCTV footage for any males possibly seen running away in the mentioned areas.
If you have any information call 101 quoting incident number 52 of January 19.
Alternatively, you can give information anonymously by contacting Crimestoppers on 0800 555 111.