The gash of freshly turned earth across a hillside was not, as might have seemed likely, one of the hundreds of landslides triggered by China's massive earthquake. It was a mass grave for some of the victims.

The only clue was a line of incense sticks and half-burnt funeral candles along the side of the road. A line of young soldiers, their faces masked against the stench, stood guard across the entrance. More troops, their uniforms protected by transparent plastic coats, squatted at the foot of the slope waiting for the next grim delivery.

An official explained the decision to dig the grave: “The authorities asked us to bury the bodies quickly because they have been dead for several days. There is no time to waste. It's already been quite a long time and now the weather is starting to get warmer.”

A digger had carved out three trenches, each about 50 metres long and 1.5 metres deep. One had already been filled. Officials refused to say how many bodies had been buried or how many they expected to receive. One official said: “We are now busy taking action to deal with this, so how many will be buried here, we really don't know yet.”

Their goal was to ensure the health of the living while respecting the dead.

The site chosen for the grave is a disused lime kiln on the edge of Libing village. It stands at the foot of a line of jagged hills in which thousands of people have died at the epicentre of the 7.9 magnitude earthquake that shook China on Monday.

An army officer said that the soldiers' task was to line the grave with lime and then lay in a body. More lime was then thrown over the corpse and it was sprayed with disinfectant. The officer hoped that this would not be an anonymous grave and that, one day, the bodies could be claimed by their relatives - if any have survived.

A photograph was taken of each corpse. Hair and blood were recorded to enable DNA identification at some later date.

Morgues and hospitals are already overwhelmed with the dead. In some areas there is insufficient electricity to provide power to keep the bodies. There is no option but a swift burial, with as much dignity as possible, in a land plunged into grief.

One doctor told a radio channel devoted to the disaster that bodies had to be disposed of as quickly as possible more than five days after the quake. The site for a grave needed to be well away from any water sources, and bodies should be disinfected and buried with lime to ensure sanitation.

The soldiers working at this mass grave, just a handful from among more than 130,000 People's Liberation Army troops deployed to search for survivors and dig out the dead, were nervous and clearly under orders to keep out prying eyes.

One said: “It is dangerous here. And we are very busy. No one can come in.”

A young farmer shrugged when asked if he was afraid to have such a large grave on a hillside close to his home. “What is the point of being frightened? If they don't bury the dead at once, then they will spread disease.”

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