A woman's car roared through the grounds of a hospital, leaving a 200-metre trail of destruction before crashing into an 11,000-volt power plant.

The driver hit the accelerator instead of the brake on her new automatic in the car park at Worthing Hospital.

She then veered off-road, ploughing into a wooden shed.

Chairs and benches were scattered in her wake as she missed a busy wooden office by a whisker.

The car then flew into the air after careering up a steep bank.

It smashed through a concrete bunker housing the transformer used to power the hospital's five-storey west wing.

The giant electrical unit, which weighs several tons, was shunted several feet from its base before the car finally came to rest.

Amazingly, the power supply was unaffected and the woman and her male passenger escaped with minor injuries.

Sue Rockall, a clinical trials data manager, was in the office when the car screeched past.

She said: "It was like a scene from an action movie. I heard the noise of revving and then a loud crash behind me. I ran to the window and looked out.

"The car took off on the bank and flew into the side of the building."

She rushed outside with a colleague, clambering through the rubble to see if she could help.

She said: "We went into the building.

"Both of them were conscious and the man was already out of the car. I put my arm around him and guided him out."

Belinda Clark, a research fellow, said: "I saw the car go straight through the shed.

"I thought it was people joyriding. The speed was unbelievable. I couldn't believe my eyes. I phoned 999."

Rescue teams arrived and began to release the driver, who was trapped in the car by her legs.

She was lifted away on a stretcher and taken round the corner to the casualty unit.

The 80-year-old woman had given a friend a lift to an appointment at the clinic in her new Suzuki Baleno.

Sub Officer Clive Innocent, of Worthing fire station, said: "The main problem was the instability of the building. We couldn't cut the lady out of the car until the building was shored up."

Despite the risk from the generator being live, firefighters went into the building to calm the woman down.

She was conscious and suffering from a back injury and shock.

Mr Innocent said: "The cables are very well insulated and it's a heavy piece of equipment so we carried on with the work. We just had to be very cautious."

Incident commander Neil Odin, of West Sussex Fire and Rescue Service, said: "After assessing the risks we decided we could free her safely without waiting for the transformer to be isolated."

The couple suffered minor injuries and were allowed to go home after treatment.

Engineers were called in to assess the damage.

Hospital spokesman Bill Banks said the challenge was how to remove the car without the building caving in on top of the generator.