Seven-times Formula One world champion Michael Schumacher was in a 'critical' condition on Monday after suffering head injuries in a skiing accident in the French Alps resort of Meribel.
Doctors operated on the 44-year-old German for the second time during the night, according to the websites of German daily Bild and French local newspaper Dauphine Libere. Bild said doctors had drilled holes in his skull to reduce internal pressure, without citing its sources.
The retired motor racing star fell while skiing off-piste on Sunday morning.
In Germany, Schumacher's accident topped news bulletins, with the bestselling tabloid newspaper Bild reporting on its website: "Schumi fighting for his life".
"He suffered head trauma with coma that needed prompt neurosurgical treatment ... He remains in a critical condition," Schumacher's agent Sabine Kehm said in a statement late on Sunday.
An official at the Grenoble hospital where he was being treated said on Monday doctors were meeting with his family but declined to give more details on the state of his health.
Christophe Gernigon-Lecomte, the director of the Meribel ski resort where Schumacher has a vacation home, said earlier the former champion was wearing a helmet when he fell and hit his head on a rock at around 11 a.m. local time (1000 GMT).
The German had been conscious while being transported first to a local hospital in Moutiers before then being transferred to Grenoble, he added.
"He was conscious but very agitated while being taken to hospital," said the director.
Schumacher Was under the care of Professor Gerard Saillant, a brain and spinal injury expert who is also president of the International Automobile Federation (FIA) Institute.
Bild reporters said Ross Brawn, the Briton who worked with Schumacher at Ferrari and Mercedes as technical director and team principal respectively, had arrived in Grenoble.
SHOCK AND PRAYERS
Leading names in motor racing reacted with shock on Twitter.
"If anyone can pull through, it's him," said Britain's triple Indy 500 winner Dario Franchitti, who is still walking on crutches after a crash in October that ended his racing career.
"Come on Michael, give us one of those race stints at pure qualifying pace to win through, like you used to. You can do it," said Schumacher's former Benetton team mate Martin Brundle.
Former Ferrari team mate Felipe Massa, who suffered a near fatal head injury at the 2009 Hungarian Grand Prix, said he was praying for his friend.
Schumacher is the most successful Formula One driver of all time with a record 91 race victories in a career spanning more than two decades.
He won his first two titles with Benetton in 1994, the year when Brazilian triple champion Ayrton Senna died in a crash at the San Marino Grand Prix, and 1995.
The German then took five in a row with Ferrari between 2000 and 2004 in what now seems a golden age for the Italian team who named a square after him at their Fiorano test track.
Schumacher left the sport last year after a less successful three-year comeback with Mercedes following an earlier retirement from Ferrari at the end of 2006. He lives in Switzerland with his wife and two children.