The police watchdog is to investigate contacts a force had with a woman and her former partner after she died and he suffered serious injuries in a shooting incident on a residential street.

Neighbours reported hearing two or three shots and saw the 46-year-old woman and 49-year-old man lying bleeding in the street. The man underwent an operation as detectives waited to interview him.

Gwent police said they were not looking for anyone else in connection with the incident, which happened on Thursday morning in Newport, south Wales, and confirmed the pair had been in a relationship.

They referred the matter to the Independent Police Complaints Commission because it had previously been made aware of problems between the couple. Police also confirmed they had recovered a weapon, but refused to confirm it was a shotgun.

Chief inspector Huw Nicholas said: "Our priority and focus is to give the appropriate and specialist support to the families of those involved and to investigate and establish what happened.

"While I am limited as to what I can say about the people involved, what I can say is it is known that they had previously been in a relationship which had come to the attention of police. For this reason we have referred the matter to the IPCC."

Sam Williams, who had been walking his dog on the street, said the woman had been hit in the chest from a few feet away. He claimed the man had then suffered injuries to his head but was still conscious and moaning.

Williams claimed a shotgun was lying nearby and that he saw spent cartridges on the floor. "I shouted to her but she didn't respond. She was gone. I just stayed with them until the police arrived."