Two French teenagers and a Ukrainian skier have died in an avalanche in the French Alps.

The children were part of a school group from Lyon - which was visiting the Deux Alpes area today.

One person is known to be seriously injured.

The French Education Ministry is understood to have reported the other members of the group - believed to be about 20 - safe.

Stuart Macdonald is an Avalanche expert and says timing in crucial in these situations: