Michael Schumacher's fans converged Friday on a hospital in the French Alps to honor the Formula One great on his 45th birthday, just days after he was critically injured in a skiing accident.

Schumacher has been in a medically induced coma since Sunday, when he struck his head on a rock while on a family vacation. Busloads of fans from Italy, where he anchored the Ferrari racing team, and Paris headed to the hospital in Grenoble where he is being treated.

Gulio Carissimo drove for four hours this morning to reach Grenoble. Wearing a Formula One Ferrari jacket and hat, he said he felt compelled to come.

"With all the joy he has given us with his victories, we had to be there," he said.

The seven-time F1 champion has undergone two brain operations since the accident, and doctors treating him are keeping him sedated and his body at an artificially low temperature to help healing.

The physicians refuse to give a prognosis for Schumacher, saying they are focused on his immediate care.

Schumacher, known affectionately as Schumi by fans, is the most successful F1 driver in history, racking up a record 91 race wins. He retired in 2012.

In a statement late Thursday, Schumacher's family thanked fans for their support.

"We all know he is a fighter and will not give up," they posted on Schumacher's website.