North Yorkshire Police said said a "dangerous dog" was out-of-control and a woman was assaulted in an incident on Sunday May 1.
Enquiries have so far failed to identify a suspect and officers have now released a CCTV image of a man they would like to speak with in connection with the Newby incident.
Officers are now urging any member of the public who can help identify the man to come forward, as he may hold important information.
Anyone who recognises the man should contact North Yorkshire Police on 101, selection option 2 , and ask for PC Jessie Landers or email [email protected]
Information can be passed on anonymously to Crimestoppers on 0800 555 111. Quote police reference number 12220073948 when providing information.