Many skiers were buried as an avalanche hit French ski resort of Tignes on Tuesday.

The avalanche fell on "a lot of people" at a busy ski slope, BBC quoted the resort police as saying.

Rescuers were unable to use helicopters because of poor visibility. They were making their way to the site on foot.

According to the BBC, the avalanche risk at Tignes was four on a scale of five, and the resort has been closed to skiers.

It had been snowing heavily in Tignes for days and mountain guides were setting off preventative avalanches to reduce the threat.
 

The Carline piste is a "blue" slope -- one of the easiest types of slope to ski on.

Bits of ski equipment could be seen on the surface of the snow covering the piste, the police said.

Last month four snowboarders were killed when an avalanche hit an off-piste area of the same resort.