UPDATE: 3.40pm

A Gwent Police spokesman said they have arrested a 26-year-old man in connection with the incident and he has been released on bail.

Police and the Welsh Ambulance Service responded to a report of an unconscious man lying on the High Street in Blackwood with a serious head injury.

The force spokesman said the condition of the man in his 20's, who was taken to hospital for treatment, has improved and officers were able to speak with him.

Gwent Police is appealing for witnesses who may have seen the incident to call 101 reference 102 4/6/2016.

UPDATE: 10.47am

A MAN was taken to the hospital with a head injury in the early hours of Saturday morning.

A Welsh Ambulance Service spokesman said they were called around 2.30am on Saturday to an area just off High Street in Blackwood.

They took a man with a head injury to the Royal Gwent Hospital in Newport.

Police were also in attendance. The High Street was closed for most of the day yesterday.