Police were called to Church Road, UB5 at 9.28am on Wednesday, 10 August, after receiving reports of a sexual assault.
Officers responded and assisted the woman. According to investigations, the alleged assault occurred shortly after 05:00hrs in a nearby underpass at the White Hart roundabout.
Specialist detectives established a crime scene and launched an investigation.
Later that day, local officers were approached by a second woman who claimed she was raped in the same underpass at or shortly after midnight.
Officers believe the allegations are linked.
“We are doing everything we can to support these women and investigate these allegations,” Detective Constable Stephen Gayfer said.
“Our investigations have led us to a man seen on CCTV who we urgently want to identify and speak with.”
“I urge anyone who recognises this man or who was in the area during these incidents and saw anything suspicious to come forward.”
Anyone with information should call 101 and mention the case number 1980/10AUG. Anonymous tips can also be given to Crimestoppers at 0800 555 111.