Officers are appealing for witnesses to a sexual assault in Portsmouth on Friday 28 June.
At about 11:15pm, a man approached a woman in her 20s as she was walking alone along Hampshire Terrace.
The man attempted to engage her in conversation, before grabbing her waist and thrusting his crotch into her.
The woman was able to push the suspect off and walk away from the incident.
Were you in the area at the time? Perhaps you were driving through the area and have dash cam footage. If so, we would really like to speak to you.
We believe this to be an isolated incident, but remind people to be extra vigilant and aware of their surroundings at night.
Anyone with information about this incident is asked to call 101, quoting 44190224079, or contact the charity Crimestoppers anonymously on 0800 555 111.
In an emergency, call 999.