Thousands of Swiss soldiers and police have been shovelling snow to erect a “ring of steel” against unwelcome demonstrators hoping to gatecrash the annual meeting of political and economic elites in the Swiss Alps.

Some 3,500 soldiers are on hand to provide security to the VIPs including German Chancellor Angela Merkel and British Prime Minister David Cameron who will descend on the Alpine ski resort in the coming days for the World Economic Forum.

Swiss Army spokesman Stefan Hofer said on Tuesday that heavy snowfall over the past two weeks made putting up some 20 km of security barriers around the heart of Davos an arduous task

“The fences need to be anchored into the ground, and we also need to keep them from being pushed over by the weight of the snow,” Mr. Hofer told The Associated Press. “We’ve had to do a lot of shovelling.”

Davos saw 40 cm of fresh snow overnight, with roadside mounds already reaching heights of more than eight feet.

“We don’t know where to put it,” said Thomas Hobi, a spokesman for the Graubuenden Cantonal (State) police, who are leading the security operation.

Still, Swiss police are expecting a calm year, with just one demonstration scheduled for Saturday.

“What’s new this year is the igloo village,” said Mr. Hobi, referring to an improvised camp built by left-wing groups inspired by the Occupy Wall Street movement. “So far, it looks peaceful. As long as it stays that way there won’t be a problem,” he added.

Meanwhile, scientists at the nearby Swiss Institute for Snow and Avalanche Research are keeping a close watch on snow-soaked slopes, lest they pose a risk to the town.

Avalanche forecaster Benjamin Zweifel said the threat level was rated “considerable” on Tuesday.

Davos is well protected against avalanches ever since the last deadly snowslide happened in 1968.

With snowfall expected to ease during the week, the threat level is unlikely to rise, he said.

Mr. Hofer, the Army spokesman, said that if difficult weather conditions persist then the Swiss Army might have to limit the number of helicopter flights it is able to conduct to ferry heads of state and government from Zurich airport to Davos.

Air patrols by F/A-18 Hornet fighter jets will be unaffected by the snow, he said.

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