LONDON - Four climbers were killed in an avalanche in the Scottish Highlands on Saturday, police said, in by far the worst incident linked to a blast of cold weather that has hit Britain.

The victims, two men and two women, were in a party of six out climbing in the Glencoe area, renowned for its beautiful landscapes. Scotland is home to Britain's highest mountains and is a popular destination for hikers and climbers.

Northern Constabulary, the force that polices the Highlands, said one woman from the same party was in hospital in a very serious condition. The sixth climber, who raised the alarm after the avalanche struck, was safe and being cared for by emergency services.

Scotland's First Minister Alex Salmond described the deaths as "an appalling tragedy."

"To lose four people from a party of six is truly devastating," he said in a statement.

Although Britain has a large and enthusiastic community of hill walkers and mountaineers, it does not have any major mountain chains. Accidents on the scale of the Glencoe incident are rare.

Elsewhere in Britain, road, rail and air traffic were disrupted by heavy snowfall that started on Friday.

Dozens of flights out of London's Heathrow Airport were canceled and British media had extensive coverage of chaotic scenes inside one passenger terminal where large numbers of people had spent the night on the floor.

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