Alonso could stay in hospital for second night

The cause of the crash has not been revealed by McLaren, triggering wild theories.

As for Alonso's condition, the 33-year-old was reported to have been initially unresponsive, and then taken first by ambulance to the circuit medical centre, and later airlifted to a nearby hospital for what McLaren called "precautionary" checks.

He is going to be observed in hospital for 24 to 48 hours.

Luis Garcia Abad

Alonso's manager Luis Garcia Abad told Spanish reporters in Barcelona that claims the driver was unwell when he stepped into the car are not true.

"The hit with the wall caused everything," he said. "He is comfortable and calm, and it was a completely normal situation.

"He is going to be observed in hospital for 24 to 48 hours," he added. "The important thing is that Fernando has always been conscious."

Asked if Alonso could miss the forthcoming Barcelona test, or the season opener in Melbourne, Abad insisted: "He's OK, I do not think there will be any problems."

Photographer's trackside account

Jordi Vidal, a trackside photographer, is quoted by Spain's AS newspaper: "Doctors tapped him on the helmet but he did not react. This lasted for about ten minutes."

Vidal captured images of Alonso sliding down the wall with the right side of his MP4-30.

According to Spanish radio Cadena SER, the newspaper cited sources at the General Hospital de Catalunya who said Alonso arrived conscious and talking to doctors.

According to Italy's Autosprint, Alonso's trainer and assistant Fabrizio Borra admitted the driver had been "agitated" after the crash, causing medical staff to administer sedatives for his trip to hospital.