POLICE want to trace a key witness after a serious sexual assault at 1.30am on July 11 in Abergavenny.

A 19-year-old woman was walking towards the castle grounds with an unknown man.

She was assaulted and fled towards Cross Street. She then spoke to a white man, in his 20s, outside a takeaway, who helped her and escorted her home.

He is not a suspect, but police would like to speak to him. Call 101 with infromation.

A 19-year-old man from Bristol was arrested in connection with the incident and is on bail.