A 30-year-old woman was assaulted in the grounds of a library in Long Eaton after leaving a nightclub.
The victim has told police she left Manhattans, in Clifford Street, at around 3am on Sunday July 6.
They walked along Tamworth Road before she said he took her into the grounds of the library and assaulted her.
She reported the incident and has been questioned about the attack and is due to be questioned again today.
Part of the grounds were cordoned off yesterday while forensic teams examined the scene.
The victim, who is from the town, told officers her attacker was white and aged in his mid-20s but was unable to give a better description.
Anyone who witnessed the assault or has information should call the police on 101, or Crimestoppers, anonymously, on 0800 555111.
