HUNDREDS of animal carcasses were exhumed from a mass grave yesterday after officials realised they had been buried in the wrong place.

Investigations following the appearance of discoloured water at the site revealed the livestock created a risk of contamination.

The grave is the second in County Durham which has had to be dug up since the foot-and-mouth epidemic began, despite claims that extensive checks are carried out before each site is chosen.

The blunder has prompted renewed fears over the safety of other burial sites used during the crisis.

A Ministry of Agriculture (Maff) spokesman said 600 sheep and 220 cattle buried at West Shipley Farm, Hamsterley, near Bishop Auckland, were dug up yesterday after it was discovered the grave was too close to an underground spring.

The carcasses had been decontaminated and would be stored elsewhere, before they are buried at the Inkerman site, at Tow Law, when it opens tomorrow.

The spokesman said: "Somebody noticed discoloured water on the surface and the exhumation is because of possible contamination to ground water and surface water.

"This area has been marked on a map as a burial site, but unfortunately the burial took place in the wrong place."

All the animals were from West Shipley Farm and had been slaughtered on site.

The burial took place on March 23 but the site was marked before the disease control centre was set up in Newcastle, and the co-ordination was being carried out from Carlisle.

The spokesman said a nearby spring had not been contaminated and there was no risk to drinking water.

But David Manning, professor of soil science at Newcastle University, told The Northern Echo last week that ground water could be contaminated with disease-carrying bacteria if carcasses were not buried properly.

And the Maff spokesman said it was unable to guarantee that other burial sites might not have to be reopened.

He said: "Measures are in place to prevent ground water contamination and there are guidelines in place before any burial site is chosen. Every step that can be taken is taken to ensure correct burial."

John Shuttleworth, who represents Weardale on Durham County Council, was horrified at the blunder.

He said: "Maff seems to be a circus run by clowns. Everything has been done in such a rush. It's just terrible.

"They just don't seem to know what they're doing and I think after this people have got to be worried. There is going to be a catastrophe if we're not careful."

The site is the second to be opened up in County Durham, after 900 slaughtered sheep and cattle exhumed at Low Houselop Farm, near Tow Law, when it was discovered they were only 15 yards from an underground spring.

An Environment Agency spokeswoman said it advised on suitable sites for burial but the final decision was taken by Maff.

She said: "Our main concerns are the potential impact on ground water and supplies.

"A few more cases may come up, but we're quite happy that these checks are in place to uncover them."

News of the exhumation came as Maff confirmed that cattle spared from slaughter last week under a change of policy had now been found to have foot-and-mouth.

A decision not to automatically cull cattle at farms next to an infected premises meant livestock at Poplars Farm at Picton, North Yorkshire, had been saved.

But a Maff spokeswoman said the cattle would be slaughtered.

An outbreak was also confirmed yesterday at Cliffe Bank Farm, Piercebridge, near Darlington, one of seven new cases nationwide.