A mentally ill man plunged a carving knife into the back of a friend as she ate her lunch in the dining room at a care home in Chippenham.

Michael Merchant had been sitting at the same table as his victim just minutes before he launched the violent attack.

The 34-year-old had gone to get himself a glass of squash from the kitchen when he opened a drawer, got out a knife and stabbed Eileen Dowdell in the back.

And he later said he didn’t now why he had done it and that he liked Miss Dowdell as she made him laugh.

Claire Marlow, prosecuting, told Swindon crown court how the incident took place at the Ash Gables residential care home on Bristol Road, Chippenham, on September 16 last year.

She said the victim was sitting in the dining room at about 12.20pm on the Wednesday finishing her lunch when Merchant entered the room and stabbed her in the back.

A member of the care staff who was in the room at the time sweeping up didn’t see what happened but heard the victim scream and fall from her seat.

The police were called and when he was questioned Merchant said he was having dinner at about midday sitting at his usual table with the victim and others.

He finished eating at about 12.10pm and went outside to sit on a bench but went back in to get the drink from the kitchen.

While there he opened a drawer and picked out the orange handled knife and stabbed Eileen in the back.

Miss Marlow said “He said he didn’t know why he stabbed her. He went on to say he liked her because she made him laugh. He said he was in a good mood all day. He said he could have killed her.”

As a result of the attack Mrs Dowdell spent a few days in hospital being treated for her injuries.

She suffered a four centimetre horizontal wound to the left shoulder blade, a broken rib and bleeding around the lining of the lung.

Merchant pleaded guilty to a charge of wounding with intent. The court heard he had a number of previous convictions for common assault and battery.

Passing sentence Judge Douglas Field said “This was a very serious assault on this perfectly innocent lady and if your mental position had been otherwise I would have been sending you to prison for many years but I am assisted having read the medical reports.”

He said Merchant was suffering from dysthymia, a form of depression, or an organic personality disorder and would be detained at a hospital where he would be treated for his problems.

The judge said he was currently being cared for at Llanarth Court in Abergavenny, Monmouthshire.

He decided not to impose a restriction order, which meant the authorities would have more control over him when he is released back into the community.