AN investigation is under way after an ambulance taking a dying man to hospital was involved in a road crash.

The patient, a 61-year-old terminally ill cancer sufferer, was being rushed to the University Hospital of North Tees, Stockton, following a deterioration in his condition.

Officials said the ambulance had its blue flashing lights on as it drove through the town.

Already critically ill, the man suffered a heart attack in the ambulance and died.

However investigators said last night it was not yet clear whether he suffered the attack before or after the collision with a Vauxhall Astra at a traffic light controlled junction at Stockton.

Police have issued an appeal to anyone who may have seen the accident to come forward.

The ambulance was travelling along Oxbridge Avenue and had reached the junction with Bishopton Road West and Bishopton Avenue when the collision occurred. The Ambulance Service launched an immediate investigation into the tragedy.

A spokesman for the Tees East and North Yorkshire Ambulance Service said: "It is the subject of a police investigation and we are conducting our own internal inquiry.

"As yet we don't know the full circumstances."

However, he confirmed: "We were carrying a gentlemen aged 61, who was described as seriously ill, to the North Tees.''

The spokesman said two ambulances were immediately sent to the scene. One vehicle was used to transport the dead patient and a crew member from the damaged ambulance to the University Hospital of North Tees.

The crewman was later released after a check-up.

The second ambulance took another member of the crew suffering from minor injuries to the same hospital.

The 19-year-old Stockton driver of the Vauxhall Astra was uninjured.

A spokeswoman for Cleveland Police said: " At approximately 9.40 hours on the morning of April 28, an ambulance was travelling north along Oxbridge Avenue, Stockton.

"Whilst passing through the junction of Bishopton Road West and Bishopton Avenue, the ambulance collided with a Vauxhall Astra. Both vehicles came to a halt in the middle of the junction.''

Cleveland Police want anyone with information to contact PC Craig Portas of the Crash Investigation Unit on (01642) 301552.