A woman was raped by a man who had offered to walk her home after a night out in Portsmouth.
The 24-year-old victim had spent last Friday evening at the Fuzzy Duck bar in Guildhall Walk before leaving alone at about 2300 BST.
She went to a nearby Subway shop where a man outside offered to walk her home. He later attacked her in the stairwell of Horatia House in Meriden Road.
A 21-year-old local man was arrested on suspicion of rape and bailed.
Det Insp Heidi Oliver said: "As part of our investigation, I'd like to hear from any women who may have been approached by a man under similar circumstances who may have tried to assault them either that night or any other.
"It might be that you didn't think anything of it at the time, or didn't think it was severe enough, but we take all reports of this nature extremely seriously."