Alps avalanche: 'It was a massive rescue operation'

Two French schoolchildren and a Ukrainian tourist have been killed in an avalanche at a ski resort in the French Alps, officials say.
They were on a mountain in the resort of Les Deux Alpes when they were swept away. The children were part of a group of 19 pupils and three staff from a school in Lyon.
A BBC producer, Sally Graham, said she was skiing down one piste when she witnessed the rescue operation on what she thought was a black advanced run that had been closed.