French Formula One driver Jules Bianchi was fighting for his life on Sunday after suffering a head injury and undergoing surgery following a crash at the Japanese Grand Prix.
The 25-year-old lost control of his Marussia on the wet track, traveled across the runoff area and hit the rear of a recovery tractor which was trying to remove a stricken Sauber, according to Formula One's governing body.
The accident caused the race to be stopped and cast a pall over drivers shocked at what had occurred.
McLaren's Jenson Button, who finished fifth, called the accident something "that you hope never happens in Formula One."
Bianchi was taken by ambulance to Mie General Hospital where he underwent surgery.
"The CT scan shows that he has suffered a severe head injury," the International Automobile Federation (FIA) said in a statement, according to Reuters.
Bianchi's father Philippe said to France 3 television that it could take 24 hours before the situation became "clearer."
The accident took place at the same point of the track, the Dunlop Curve, where Adrian Sutil had aquaplaned off into the tire barrier just moments earlier on lap 42. He was watching his car being removed when the second incident took place.
There was no podium celebration after the race and the champagne was left unsprayed. The top three drivers just clicked bottles before putting them back on the ground, according to Reuters.
"It's obviously a real anti-climax to hear that one of our fellow colleagues is seriously injured so that's really the main worry," Mercedes' race winner Lewis Hamilton said to the BBC. "You could see some commotion and the car was really badly damaged on the right. We just hope he's OK."
"I'm not thinking about the race, I'm thinking about my colleague," said his team mate and title rival Nico Rosberg, according to Reuters. "I've been given some information and it seems very, very serious. I'm hoping for the best."
Bianchi is a graduate of Ferrari's young driver academy.