"There's a real and serious risk of a leak causing toxic gas to escape," said Remy Pautrat, the chief local government officer: "The gases ... are lethal."

Residents living within three kilometres (1.7 miles) of the Vimy depot near Arras had to leave their homes, sometimes protesting angrily, so that the munitions could be removed to be made safe.

A fire fighter carries a fire hose as he walks past the depot of World War I munitions in Vimy, northern France, Friday April 13 2001. The French government on Friday ordered a 10-day evacuation of about 12, 500 people living within a 3-kilometer (about 2 mile) radius because of fears that a stockpile of World War I munitions could explode or leak toxic chemicals, including mustard gas. (AP Photo/Michel Spingler)

The dump contains 173 tonnes of munitions, among them some 16,000 British, German and French shells, nearly all containing highly toxic mustard gas or phosgene, the two chemicals most widely used in the war, local officials said.

Civil defence units, including special chemical squads, could be seen Friday working at the cordoned-off dump, where thousands of rusting munitions have been lying for decades.

Vimy Ridge was the scene of a ferocious 1917 in which Canadian forces stormed and eventually took heavily fortified German positions in an heroic assault.

The present site was set up in 1967 as temporary storage for tons of missiles from World War I that are still dug up every year in France.

Some 500 tonnes of conventional weapons were removed two years ago in an operation, killing two disposal experts.

On Friday, some 700 firefighters, more than 450 French soldiers, special and local police were mobilised to clear the area and secure the dangerous site.

In the biggest operation of its kind in France, the munitions were to be transported by refrigerated vehicles to a military camp at Suippes, 200 kilometres (120 miles) to the east, to be unpacked and restocked in safer conditions.

Police and firefighters went from door to door with warrants ordering sometimes reluctant and vehement local residents to leave their houses by 7:00 pm (1700 GMT) for 10 days.

Staffed reception centres with some 15,000 beds were set up to accommodate them. Psychological counsellors were in attendance.

By 7:00 pm eighty percent of local inhabitants had been evacuated.

Authorities requisitioned 130 buses for the operation.

Trucks and temporary pastures were requisitioned to move herds of cattle.

"The munitions won't be destroyed because there isn't any place in France for this kind of operation," said a local official: "They will be reconditioned in maximum security conditions."

A report commissioned by the French interior ministry earlier his year found that wooden crates containing the weapons were in dangerous states of disrepair, presenting a growing risk of explosion.

"Some crates have been showing signs of cracking. Our experts concluded there was a risk of shells touching each other. As a result there are serious risks for the local population, especially from toxic chemicals which are still active," a ministry statement said.

"At the end of 10 days there'll be no chemical weapons left here," said Christian Masson, a fireman working at a crisis centre set up in Arras.

"I know this news is going to take people aback, but it is a serious operation because of the serious risks involved," Interior Minister Daniel Vaillant told a news conference in nearby Arras.

Copyright 2001 Agence France Presse

###