A 27-year-old man has been arrested after a fatal assault in the centre of Cardiff.

The victim, named by South Wales Police as 21-year-old Asim Khan from Grangetown, was treated by emergency services after the incident in St Mary’s Street at around 4.50am on Sunday.

Police said a local man had been arrested in connection with the incident, but not what he had been held on suspicion of.

Detective Superintendent Richard Jones said: “A young man has tragically lost his life early this morning and we are doing all we can to bring those responsible for the murder of Asim Khan to justice.

“CCTV shows a disturbance which starts in the street near McDonald’s and moves towards the Oxfam store where Mr Khan sadly collapsed having sustained a wound as a result of being stabbed.

“Significant police inquiries are continuing in the area and we thank the local community, including businesses and visitors, for its understanding while a number of cordons remain in place.”

Witnesses have described the suspect making off initially in the direction of Wood Street, and then towards Penarth Road at the rear of Cardiff Central railway station.

Anyone with information is asked to phone 101 and quote reference number 1900265784.