British mother and son killed by avalanche on Mont Blanc in France ...

The family of a British mother and son killed by an avalanche on Mont Blanc in France have said they are "beyond heartbroken" following the "tragic accident".

Kate Vokes, 54, and her 22-year-old son Archie were found dead under snow by mountain rescuers around Saint-Gervais, a resort near Chamonix in the French Alps, on Thursday afternoon.

The family has said in a statement: "We are beyond heartbroken at the loss of our beloved, wonderful Kate and Archie.

"Words cannot express how terrible we all feel nor the hole in our lives that has been left by this tragic accident."

The statement adds: "Kate was chair of the Oglesby Charitable Trust, a director of their family-owned property company Bruntwood, deputy chair of the Royal Exchange Theatre and a trustee of charities Shared Health and Focussed Care.

"Archie was a personal trainer at Form in Manchester and in the previous year had achieved his level 1 ski instructor qualification in Canada."

Officials have said they believe the avalanche may have been triggered by two ski tourers who were uphill from Kate and Archie Vokes.

A manslaughter investigation has been opened and the cause of the avalanche is being investigated.

The mother and son had been skiing with three other family members and a freelance ski instructor, whom they had known for several years, the Bonneville Public Prosecutor's Office said on Friday.

Read more:Man charged with attempting to murder two policewomenLuton captain shares update after cardiac arrest

No one in the family was wearing an avalanche transceiver, which emits a silent signal that can be detected if buried under snow.

A major search and rescue operation was immediately launched, involving around 20 rescuers, two dog teams, a doctor and two helicopters.

The team rescued one other injured person, reportedly an instructor, and five further people.

A 31-year-old hiker was also killed on a separate slope.

A Foreign Office spokesperson said after the deaths: "We are supporting the family of two British people who died in France and are in contact with the local authorities."