AN investigation is underway into how a bus and a wagon came to collide, injuring 13 people.

A pregnant woman was among those taken to hospital on Monday afternoon, after the bus careered into a bus stop before smashing into a tree.

Fortunately, there was no one standing at the bus stop at the time, and no passers-by were hurt.

However, the driver of the lorry had to be airlifted to hospital after complaining of back pain, and the driver of the bus, along with 11 passengers, were also taken to hospital for treatment.

Three were taken to the University Hospital of North Tees in Stockton, and ten to the University Hospital of Hartlepool, but none suffered serious injuries and all were later released.

Cleveland Police are appealing for witnesses to come forward with information about the crash.

The Arriva 230 service between, Hartlepool and Sunderland, was travelling along the A179 Easington Road in Hartlepool at about 3.35pm on Monday when the incident happened.

The bus was heading out of Hartlepool, towards the Clavering area, when the two vehicles collided.

The emergency services, including a number of ambulances, were at the scene soon afterwards, and the road was briefly closed while the injured - all described as "walking wounded" - were dealt with.

A Cleveland Police spokeswoman said: "Our main priority on Monday was making sure everyone was OK, and getting the road cleared and traffic flowing normally again, as it was approaching rush hour.

"However, investigations are ongoing today and we would ask anyone with information, who has not yet come forward, to do so."

A spokesman for Arriva said it was too early to make a statement, but said the driver of the bus had been given some time to recuperate at home.

He said: "We are examining the bus at present, but there is significant damage to the front and rear of it.

"Our investigation is still ongoing."

Anyone with information should call Cleveland's road policing unit on 01642-301552.