A 21-year-old woman was subjected to a serious sexual assault in Corby.
The attack happened in Lyveden Way, close to the junction with Butland Road, at some point between 4.15am and 4.45am on Saturday (August 19).
The victim was assaulted by a man who is described as black, 6ft or just under and of an average build.
He was wearing a red top.
Det Insp Emma Nealon said: “This was an extremely rare incident, but officers are asking people to be vigilant and, as such, we have put on extra patrols in this area as a precaution.
“We want to hear from anyone that might have seen either the victim or any males matching this description in the area around that time as well as anyone that might have been passing through in a vehicle, or seen anyone fitting that description in the Corby area.
“Anyone with information should call Northamptonshire Police on 101 or Crimestoppers, in confidence, on 0800 555111.”