Modern Europe

Archaeologists say there is "compelling" evidence they have found the mass burial site of British and Australian troops who were killed during World War I.

They believe the bodies of up to 400 soldiers remain in unmarked graves in northern France near the site of the Battle of Fromelles.

It is the largest discovery of its kind and the Australian, British, French and German authorities must now decide whether to proceed with a mass exhumation of the soldiers' remains.

The Battle of Fromelles was an unmitigated disaster.

It was conceived as a ruse to divert German attention away from the campaign on the Somme in July 1916.

Burial pits

The British and Australians launched an assault on heavily fortified positions in broad daylight.

Although they fought bravely they suffered heavy losses.

The British withdrew and the Australians had to fight their way back through the German lines.

A second assault was cancelled, though the Australians were not told and they lost more men.

A geophysical survey has located burial pits where hundreds of soldiers were buried after the battle.

Dr Tony Pollard, the director of the Centre for Battlefield Archaeology at Glasgow University, has just returned from the site.

"To my knowledge this is the largest unmarked mass grave from the First World War to be discovered in modern times," he said.

"There have been multiple graves in the past, but they've been maybe twenty to thirty men. We're talking here of somewhere in the region of 400 men according to the German records that we have".

He said a metal detector survey revealed a number of artefacts including metal objects with Australian Army insignia on them.

"The only way they could have got there really is on the dead bodies of Australian soldiers," he said.

"The bodies haven't been disinterred and buried elsewhere. We believe there's strong evidence that the bodies are still buried in that field."

Visit from Hitler

In Australia the battle is regarded as one of the most significant in its history.

Dr Pollard said, among Australians, the Battle of Fromelles is talked about in the same breath as Gallipoli.

"It's a huge national disaster. Within the twelve or fifteen hours of the battle 5,500 Australian soldiers were either killed or wounded."

But he said it also held strong significance for the British.

"We tend to forget the Battle of Fromelles over here because it's overshadowed by the Battle of the Somme.

"But upwards of 1,500 to 2,000 British soldiers were killed or wounded in that same attack and several hundred of those may be in those grave pits."

It was the first time its troops had seen action on the Western Front, and it is seen as an example of how the Empire was prepared to sacrifice its colonial troops with little thought about the consequences.

It is believed Adolf Hitler, then a corporal in the Bavarian reserve infantry, ran messages behind the German lines during the battle.

And the bunker Hitler visited in the 1940s when he came to occupied France is said to be just a few hundred yards from the burial site.

The mammoth task of trying to work out who might buried there has already begun.

Historian and author Peter Barton, who is also part of the team working on the project, said: "We are potentially speaking of 399 sets of remains - a very costly and very lengthy exercise, as indeed the excavation itself would be."

The next decision will be whether to exhume the bodies and bury them with full military honours.

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