Cape Town - Fernando Alonso has been taken to hospital by helicopter after crashing in his McLaren during Formula One preseason testing on Sunday.
McLaren said on Twitter: "Fernando is conscious and is speaking. He has been airlifted to hospital for further checks."
Track officials at the Barcelona-Catalunya circuit said Alonso went off at turn three and hit the wall. They said he was transported to hospital "to continue with medical tests" after being treated at the circuit medical center.
McLaren has been plagued by technical problems this preseason after switching to Honda engines ahead of the upcoming season.
Neither the team nor track officials have reported the cause of the crash.
Alonso, 33, rejoined McLaren this season after a disappointing fifth and final campaign with Ferrari. He won back-to-back world titles with Renault in 2005 and 2006 before spending one season at McLaren in 2007.
Ferrari tweeted "Get well soon Fernando."