Police are investigating the alleged rape of 17-year-old girl in the university area of south Belfast.
The suspected serious sexual assault near Queen's University Student's union comes amid community fears the area is becoming a rape hot spot.
More than 20 women claim to have been targeted in the wider south Belfast area in the last six months.
The girl was allegedly assaulted at the corner of University Road and Elmwood Avenue while a Halloween ball was taking place in the nearby students' union.
Police have asked anyone who attended the event and noticed anything suspicious to get in touch.
They are looking for a 20-year-old man, with short dark brown hair, 5ft 4ins tall and of stocky build.