Investigation into avalanche deaths

Tributes have been paid to three Britons, including one of the UK's most respected climbers, who were killed in an avalanche near a French ski resort.

The British Mountaineering Council said climbers were "shocked and saddened" to hear that its former general secretary, Roger Payne, was among those who died near the Alpine resort of Chamonix.

The BBC's Imogen Foulkes explains that the avalanche could have been triggered by one of the climbers.