Gwent Police are investigating after a 16-year-old girl was assaulted in an alleyway.
The attack took place between midnight and 3am on Sunday in Maesycymmer between Tabor Road and Main Road.
Police have said the teenager was not seriously injured.
The attacker is white, aged between 19 and 25 and is of average build. He has spiky, mid-length, blond or sandy coloured hair and was wearing light blue jeans and a white top.
Anyone with information about the attack should contact Gwent Police on 101 or Crimestoppers anonymously on 0800 555 111.