AS A military helicopter hovered over the diamond fields of Chiadzwa in eastern Zimbabwe, police on horseback moved in with attack dogs to remove thousands of illegal diggers who had poured in, hoping to get rich.

The diggers resisted, attacking the dogs with iron bars. The police opened fire from the helicopter, routing them. By the time it was all over, dozens lay dead.

Last week the fields where the slaughter took place were silent and largely empty, sealed off by soldiers to stop anyone returning. In nearby towns and villages, however, the ruthless crackdown that began last month carried on.

The military threw up road-blocks and searched vehicles. Anyone found in possession of foreign currency was arrested on suspicion of being an illegal digger or diamond dealer, taken back to the fields, beaten and made to fill in the holes they had dug with their bare hands, without food and water.

“They are taking people without regard to whether they are dealing with diamonds or not,” said Trust Mannda, the regional co-ordinator of Zimbabwe Lawyers for Human Rights. “We condemn it in the strongest terms.”

Nobody knows for sure the numbers the police killed. Local sources said more than 50 people had probably been shot and hundreds injured in the onslaught, called Operation No Return by the military. Yesterday 20 unclaimed bodies were still piled up at the nearby Mutare provincial hospital, awaiting identification. Other bodies lay unclaimed in the surrounding forests. Yet more were buried in collapsed tunnels inside the diamond fields.

While human rights groups condemned the crackdown, diplomats concluded that it was another sign of President Robert Mugabe’s desperation to find new sources of money to pay the security forces whose support he needs to stay in power.

That need was sharply brought into focus last week when soldiers rampaged through Harare looting, breaking shop windows and seizing cash from street dealers after being unable to withdraw their wages from banks.

The rioting soldiers chanted slogans against Gideon Gono, the deeply unpopular Reserve Bank governor, on the day that Mugabe defiantly reappointed him for a further five years.

It was the first time since independence in 1980 that soldiers had broken ranks and publicly protested against Mugabe’s regime but riot police quickly crushed them and several soldiers were arrested. For Mugabe the timing could hardly have been worse.

His ruling Zanu-PF party holds its end-of-year conference this week. The 84-year-old leader will be seeking a show of unity. But all indications point to a party demoralised and in disarray and Mugabe has been forced by a cholera outbreak that has killed nearly 600 people since August to declare a national health emergency and appeal for international aid.

There was even talk yesterday of postponing the conference for fear that the cholera, caused by the collapse of the country’s water and sewerage system, would create havoc among the 4,000 delegates expected.

Yesterday Gordon Brown joined international figures in condemning Mugabe. He said that “enough is enough” and the government was “broken” and unable or unwilling to protect its people.

Brown’s remarks followed a statement by Condoleezza Rice, the American secretary of state, that it was “well past time” for Mugabe to leave office. Mugabe is also coming under pressure from some African states.

With the economy broken, the currency worthless, hunger stalking the land and a growing humanitarian and health crisis, the Chiadzwa diamond fields could be one of the regime’s last sources of foreign currency and one way of keeping the military happy.

The fields used to be managed by De Beers, the South African mining giant. After independence, De Beers sold its franchise to African Consolidated Resources (ACR), a British company. Two years ago the government confiscated the fields and handed them to the state-owned Zimbabwe Mining Development Corporation, which never got round to doing any extraction of diamonds.

Instead, thousands of Zimbabweans and other Africans swarmed over the 170-acre site in one of the greatest diamond rushes the continent has seen in modern times.

It is believed that hundreds died as the fields fell into lawlessness and violence. Diggers began arming themselves with handguns. Sometimes there were as many as 4,000 hand-panners searching for diamonds. Among them were army and police officers who had deserted but were still in uniform. Local children stopped attending school and many schools failed to open because teachers and pupils were digging in the fields.

While the government was not formally involved in extracting the diamonds, members of its corrupt elite were enriching themselves. Using their own diggers and traders, to whom they paid paltry sums, they sold the diamonds outside the country, collectively touching 10% of the fields’ total turnover. It was enough to put tens of thousands of dollars a month into their pockets, according to one conservative estimate.

The majority of the diamonds from Chiadzwa were sold directly to foreign buyers, however, and ended up in the Middle East, easily distinguishable by their colour and frostiness, whatever the paperwork gave as their origin.

Zimbabwe is a participant in the Kimberley Process, which was established in 2003 to combat the illicit traffic in diamonds from conflict zones. It could easily be argued that its association with so many deaths and the enrichment of one of Africa’s nastiest regimes has put the country’s gems in much the same category as the notorious “blood diamonds” that once fuelled conflicts in Congo and Sierra Leone.

In October, Gono publicly declared that if Chiadzwa was properly managed, as much as $1.2 billion a month could be realised by the state from diamond sales - enough, he said, to turn round the collapsing economy. It is estimated that the government has been losing about $400m a month in revenue from smuggling.

A few weeks ago Gono went looking for cash in Russia, which in July vetoed a United Nations security council resolution to impose sanctions on Mugabe and his inner circle.

Authoritative sources said Gono was courting Alrosa, Russia’s state-owned diamond mining and marketing corporation. He was hoping to sell the conglomerate - which controls as much as 18% of the world diamond market - a big stake in the fields.

Gono received a sympathetic hearing. At the end of November a top Alrosa executive visited Harare at Gono’s invitation to explore a deal. But the word this weekend was that the Russians had got cold feet. Gono’s hopes of pulling off a deal to ensure that, at the very least, the military would be paid were scuppered.

“It is tragic that people are dying of cholera and violence when there is this wealth of assets available to the country,” said Andrew Cranswick, chief executive of ACR.

“All it requires is respect for law and order and a legal joint-venture mining programme by the government of Zimbabwe and international mining companies and there would be plenty of money available to solve these critical economic and humanitarian problems.”

Zimbabwe has been without a legal government since the opposition Movement for Democratic Change won control of parliament in March. The political deadlock, nightmare of cholera, water and power shortages, endless queues, worthless money and empty shops still do not seem to have an impact on Mugabe, who remains impervious to pressure.

He did have a 30-minute meeting with Ban Ki-moon, the UN secretary-general, in Qatar a week ago, however.

Perhaps it was the “last opportunity” for a peaceful resolution of the crisis, said the Tanzanian ambassador who helped to set up the meeting, echoing fears of a violent upheaval as the country nears breaking point.

A COUNTRY IN TATTERS

Cholera 575 dead; 12,700 suspected cases

HIV/Aids 1.3m living with Aids; 1m orphans created by the disease; 140,000 deaths

Malnutrition now afflicting 45% of population

Life expectancy lowest in world - 34 for women and 37 for men

Inflation 231m%: 200m Zimbabwe dollar banknote to be issued

Unemployment 80%

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