A murder investigation is under way after a 20-year-old man, jailed last year for causing the death of a Liphook teenager by dangerous driving, died in

hospital on Sunday.

Dwayne Ayres, from Yateley, who had recently been released from prison, was jailed for two and a half years after being convicted of causing the death of two teenagers, by dangerous driving.

Mr Ayres died at Frimley Park Hospital in the early hours of Sunday morning.

On March 16 last year, Mr Ayres crashed his Peugeot 206 into a tree outside Calthorpe Park School in Fleet. Callum Forbes, 15, from Liphook, and John Bryant, 18, who were in the car with him, were killed and two other teenage passengers were seriously injured.

Winchester Crown Court heard how Mr Ayres had lost control of the car while driving at 66mph in a 40mph zone and that blood samples revealed he had taken cocaine shortly before the crash.

Crash victim Callum Forbes attended Liphook Junior School and later went to Bohunt School, but a series of terrible disappointments in his short life turned him from an intelligent, caring boy into an out-of-control tearaway, according to his family at the time.

Grandparents Jackie and Frank Jones were distraught at Callum's death and blamed Hampshire County Council's social services department for not listening to their pleas to find Callum a residential boarding school where he would be distanced from drugs and receive an education, which they believe would have saved his life.

The family buried Callum at St Mary's Church, in Bramshott, on March 24 last year – just a stone's throw from his grandparents' home.

Nine people were arrested in connection with the death of Mr Ayres.

Following an incident at an address in Hook, Holt Way and a property in nearby Four Acre Coppice were cordoned off by police officers.

Detectives from Hampshire Constabulary's major crime department have since released two 21-year-old men, a 19-year-old man, a 20 year-old man and a 27-year-old man without charge.

On Tuesday, three people were charged with aggravated burglary: Lucy Ayres, 28, from Crondall, Stuart Young, 21, of Berkshire,

and a 16-year-old male.

All three were due to appear at Aldershot Magistrates Court on Wednesday morning.

A man, 24, held on suspicion of murder, was bailed until January 14, 2009.

A post mortem examination conducted by Home Office pathologist Huw White at the Royal Hampshire County Hospital, in Winchester, found that Mr Ayres had died of a stab wound.

Det Chief Insp Colin Mathews, of Hampshire Constabulary, said: "A number of lines of inquiry are being investigated at this stage.

"We would urge anyone with information to contact us as soon as possible and in confidence."

Mr Ayres leaves a partner and an 18-month-old baby.

In a statement, his family said: "Dwayne was a lovely, caring son to Vanessa and will be greatly missed by all those who knew him and he will always be remembered.

"He had just started to live his new life with his love Emily and their son Richard.

"We would ask everyone to respect their privacy at this time."

Anyone with any information should contact the Operation Larkspur team on 0845 0454545

or anonymously by calling Crimestoppers on 0800 555111.