A TEN-YEAR-OLD boy may have witnessed his mother being killed, detectives revealed last night.

The boy was yesterday being interviewed by police investigating the death of 37-year-old Joanna Luke.

The mother-of-two was fatally injured after being struck on the head in her home at Priory Gardens, Willington, County Durham, on Sunday night.

Detectives said the youngster was at home at the time of the attack and may have vital information about what happened.

Last night, a 45-year-old man, believed to be Mrs Luke's husband, Michael, was still in hospital awaiting psychiatric tests.

The landscape gardener, formally from Brandon, County Durham, was arrested at the scene on suspicion of murder.

He was later released and admitted to hospital. He has not been charged.

The couple, who were married for 18 years, moved to the detached home on the quiet residential street 18 months ago from Langley Moor, County Durham.

Friends said that Mrs Luke planned to move out of the marital home - which had been put up for sale.

Acting Detective Superintendent Neil Malkin, who is leading the inquiry, confirmed that Mrs Luke's son was interviewed yesterday.

He said: "He was in the house on Sunday evening, and we are trying to find out whether or not he may have seen anything that may be able to help with the investigation."

The boy and his 17-year-old sister, who was enjoying a night out with friends in Durham when the incident happened, were being comforted by their grandparents last night.

Although neighbours and friends have been helping officers piece together Mrs Luke's last movements, police are appealing for anyone with information to come forward.

Witnesses are asked to call Durham Police on 0845 60 60 365, or Crimestoppers on 0800 555111.