As police wait for the results of drug tests on a Winchester teenager who died after stabbing himself in the heart, his parents are struggling to understand what drove him to do it.

Cathy and Steve Hynard have told the Hampshire Chronicle about the fateful night and the bizarre behaviour of 16-year-old son, James.

When he returned from his part-time job at the Baker's Oven, in the High Street, on Thursday in last week, their "gentle, caring boy" had become "paranoid and aggressive". Later that night, James stabbed himself in the heart with a pair of scissors in front of his father in the living room of their Greenhill Road home.

The next day, he was due to go on a camping holiday to Cornwall with family and friends.

His parents, who are divorced, remain stunned and puzzled.

Cathy said: "It was completely out of the blue, a complete change in his personality. He was always a gentle, caring boy. But when he came home that night, he was frightened.

"He thought he was going to be beaten up and he thought he had been followed home. He was completely paranoid. We were reassuring him, but he was frightened. Looking back, the things he was saying didn't seem rational."

Steve was forced to restrain James as his behaviour became increasingly worrying. "As the evening progressed, he became violent towards his sister and towards me," he said.

"In the end, I had to sit on him to restrain him and we phoned for an ambulance. He said he was seeing people coming out of the walls and the TV. He was looking at us as though we were complete strangers."

The ambulance took him to hospital where he was checked over and discharged back into his family's care. "We took him home and tried to talk to him," said Cathy.

"I asked him if he wanted to go to bed and he agreed to but that didn't work. He came down in his dressing gown and we tried to feed him.

"It was while we went to the kitchen to make him some toast that it happened. He basically died in my arms."

James was rushed to the Royal Hampshire County Hospital, but staff were unable to revive him and he was pronounced dead at 1.55am on Friday.

Police, who are not treating his death as suspicious, suspect drugs may be a factor and the family are now facing the agonising wait for a toxicology report to help them understand what was behind his bizarre behaviour.

"It was just completely unreal, like a film, so completely bizarre and so horrifying," said Cathy.

"There are questions everyone needs to be answered so we can understand what caused his mood to be so changed. He was a normal, happy, gentle and friendly boy. There were no signs at all, prior to that evening."

Friends and family are now struggling to comes to terms with his death.

They remember a popular boy with an active social life, kept goal for the school football team, enjoyed playing the piano and relished taking part in a recent school production of Tin Pan Ali.

James had just left Westgate School, Winchester, after taking his GCSEs and was planning to go on to Peter Symonds' College in September.

Cathy said: "We are remembering his happy times. We are trying to keep those in everyone's minds rather than the horror of that day.

"We have been hugely comforted by his friends and our family and I would like to say how helpful and supportive the police have been."

Shocked by the events of that night, friends and neighbours placed floral tributes and messages outside the family's home.

One read: "I can't begin to understand. We all loved you so much. That love will continue and you will not be forgotten."