A racing driver has suffered life threatening injuries after a crash during testing at Duxford in Cambridgeshire.
Maria de Villota, a test driver for the Marussia F1 team, was taken to hospital after her car collided with a lorry.
Gary Sanderson, a spokesman for the East of England Ambulance Service, said: "A woman has sustained life-threatening injuries and following treatment at the scene by paramedics, she has been taken to Addenbrooke's Hospital for further care."
The accident is said to have happened at low speed after Villota pulled off the track following a lap during which she reached speeds of about 200mph.
Chris Mann, a presenter on BBC Radio Cambridgeshire, witnessed the accident.
He said: "She got into the car, fired it up and did a test run at probably about 200mph in the rain. The car was slightly misfiring but there didn't seem to be any concerns.
"She came back into the area we were in with the engineers. She slowed down but then suddenly, inexplicably accelerated through the crowd and smashed into the side of the truck."
The 32-year-old, originally from Madrid, was taking part in the first of two days of testing at the site.
In a statement, a spokesman for Marussia said: "At approximately 09.15am, the Marussia F1 Team's test driver, Maria De Villota, had an accident in the team's MR-01 race car at Duxford airfield where she was testing the car for the first time.
"Maria has been transferred to hospital. Once her medical condition has been assessed, a further statement will be issued."
As news of this morning's accident spread, Formula One drivers used social networking sites to offer messages of support to De Villota.
Writing on his Twitter account, McLaren driver Jenson Button said: "Terrible accident For Maria de Villota, Marussia F1 team test driver. My thoughts are with Maria and her family at this very difficult time."
De Villota's compatriot Fernando Alonso, who drives for Ferrari, also took to his Twitter account, saying: "I just got home and found out Maria's accident, we called the family and hopefully we will know more soon ! All my energy with you!"
Toro Rosso driver Daniel Ricciardo tweeted: "Let's put Maria de Villota in our hearts today