DHAKA: Investigators in France are examining a camera which had been fixed to the ski helmet of injured Formula 1 driver Michael Schumacher, media reports say.

Authorities were hoping the device may reveal clues about the circumstances of his skiing accident in the French Alps, a source told.

Police also interviewed Schumacher`s teenage son, who witnessed the crash, reports BBC.

Fans earlier held a vigil outside the French hospital treating the F1 legend, to mark his 45th birthday.

Ferrari supporters gathered at the clinic in the city of Grenoble and held a one-minute silence on Friday afternoon.

Schumacher`s family said in a statement they had been moved to tears and "utterly overwhelmed" by the "incredible sympathies" shown by the fans.

The German champion, who retired in 2012, is in a medically induced coma after suffering head injuries during a fall in the resort of Meribel last Sunday.

His helmet cracked on impact when he hit a rock while skiing off-piste.

He remains in a stable but critical condition after two operations to remove blood and pressure from his brain.

Doctors confirmed on Tuesday that Schumacher had shown signs of improvement, but was still "not out of danger".

They ruled out giving a prognosis for his condition in the coming days and months.

But it is medically possible for someone to spend several weeks in an induced coma and make a full recovery.

BDST:  1311 HRS, JAN 04, 2014
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