A jogger was sexually assaulted by a hooded teenager in Raunds.
Police have launched an appeal after the incident in Fairoaks Drive between 8.45pm and 9.05pm last night (Thursday).
As the victim was running she passed a teenager on his bicycle.
He then changed direction, rode past her, grabbed her inappropriately and pushed her to the floor.
A police spokesman said the offender is described as white, in his late teens, wearing a black top with the hood up and carrying a white drawstring bag.
Anyone with any information should contact Northamptonshire Police on 101.
Information can also be submitted anonymously to Crimestoppers on 0800 555111.