As Robert Mugabe and his wife Grace flaunted their presence in Rome last week - he as a controversial guest at a United Nations food summit defending the brutal rule that has left Zimbabwe bleeding and impoverished, she closeted in a luxury hotel - a powerful group of military and security chiefs masterminding the president’s election battle was leaving nothing to chance.

Led by Emmerson Mnangagwa, a sinister former spymaster known as “the Crocodile” who recently took control of the ruthless Joint Operations Command that now effectively runs the country, a violent crackdown was stepped up against the opposition and the voters who had the temerity to support it.

Morgan Tsvangirai, leader of the opposition Movement for Democratic Change (MDC), was harassed and threatened as he attempted to hold rallies before the presidential run-off on June 27. MDC supporters were beaten and jailed. At least 65 have been murdered since the disputed first round of the election in March.

Diplomats who tried to investigate the violence were attacked. Aid agencies attempting to feed the victims of Mugabe’s disastrous policies were banned – all the better to hide the humanitarian disaster and political thuggery from the outside world.

“We are dealing with a desperate regime here which will do anything to stay in power,” said James McGee, the American ambassador, after an incident in which police held five American and two British diplomats.

The misery of the Zimba-bwean people was a world away from Rome where Mugabe, 84, and Grace, 39, were leading a 60-strong delegation, the biggest from the African continent barring Egypt, to the food summit.

According to sources close to the Zimbabwe delegation. a third of Mugabe’s cronies alone ran up a £12,000 bill at the five-star Ambasciatori Palace hotel on the Via Veneto, which has hosted stars such as Liza Minnelli, Sean Connery and Sofia Loren.

Mugabe and his wife followed in their footsteps by staying in a £480anight, fifth-floor suite boasting two bedrooms with three king-sized beds and two pink marble bathrooms complete with a vast whirlpool bath.

Wary of provoking negative headlines about her notorious passion for shopping, Grace remained in the hotel for much of the visit and instead sent out members of the delegation to make purchases on her behalf.

The couple brought a personal uniformed butler and two chefs from Harare. The chefs, wearing surgical-style face masks, worked from a kitchen separate from the hotel’s restaurant. Asked whether his boss feared being poisoned, George Charamba, Mugabe’s spokesman, replied: “Many people are his enemies, but that’s not the reason. He follows his own diet.”

Mugabe used his speech at the UN Food and Agriculture Organisation’s summit to blame the suffering facing millions of his people on sanctions masterminded by Britain. It was a familiar cry from a leader who has sought to paint his opponent Tsvangirai as a British puppet.

Food has become a blatant tool for vote-rigging. McGee, the US envoy, said that to receive food aid, MDC supporters had to surrender their identity cards to government officials who would hold on to them until after the election, depriving them of their vote. But supporters of Zanu-PF could keep their identity cards and so were free to vote. “It is absolutely illegal,” he said.

He spoke out after the authorities had suddenly ordered aid groups to halt their operations, even though they are the only lifeline for millions who depend on them for food and supplies as the economy crumbles.

Without their help, aid deliveries to more than 4m people will be severely hampered. More than half the population scrapes a living on less than 50p a day and average life expectancy is just 35, according to the UN.

Many impoverished Zimbabweans will now be entirely dependent on Mugabe’s government and Zanu-PF, his ruling party. The struggle to survive, the authorities calculate, will force them to vote for him.

Jasmine Whitbread, chief executive officer of Save the Children, said: “Without this lifeline, levels of malnutrition and disease will increase and children could die as a result.”

After losing to Tsvangirai in March, Mugabe contemplated standing down. But a small circle of military and security chiefs, worried about their own fate, convinced him to stay by assuring him they could deliver a second round victory.

To achieve this they have set up what amounts to a military operation designed to force those Zimbabweans who had deserted Mugabe back into his Zanu-PF camp.

Mnangagwa, 61, is Mugabe’s electoral mastermind. A ruthless operator, he was security supremo during the notorious “Gukuruhundi” slaughter of 20,000 members of the minority Ndebele tribe in the early 1980s, during the early years of Mugabe’s rule. The fate of the two men has been inextricably bound together since the killings.

While Mnangagwa plans the overall strategy, the organisers of the violence on the ground are two senior serving officers – General Constantine Chiwenga, commander of the Zimbabwe defence force, and Augustine Chihuri, the chief of police.

Chiwenga in particular was instrumental in persuading Mugabe not to quit. Even before the March election he had said the army would not support an opposition-led government. He and his wife Jocelyn, a one-time barroom waitress, are among those in the leadership who took over white-owned farms.

In 2002 Jocelyn was quoted as having told a white farmer, whose property she coveted, that she had not “tasted white blood since 1980” - the year of Zimbabwe’s independence - and missed the experience.

Chihuri, the police chief, is also a staunch Mugabe loyalist who is credited among Zimbabweans as having done more than anyone else to politicise the police force by turning it into an arm of Zanu-PF. “He owes everything to Mugabe,” said an informed source. “He is Mugabe’s hatchet man in the politburo – very tough, very ruthless, very hardline.”

In his role as police chief, a position he has held since 1993, he has presided over the brutal suppression of many antigovernment demonstrations.

These two senior officers have divided overall operational command geographically between Air Marshal Perence Shiri, covering Mashonaland in the north, and army commander General Philip Sibanda, who covers the southern provinces of Matebele-land and Masvingo.

Whether the “securocrats” can beat and rig their way to victory remains uncertain. As Mugabe headed home from the luxuries of life in Rome at the end of last week, some in Zanu-PF were questioning whether the violence would prove counter-productive on polling day.

Mugabe, however, showed no signs of backing off from the fight of his life and his military chiefs were pressing murderously on to keep him in power.

Additional reporting: Frederick Cowper-Coles

Reign of terror

- 65 people killed since first round of voting on March 29

- About 25,000 displaced

- Thousands injured

- Opposition leader and western diplomats briefly detained

- MDC supporters forced to surrender IDs needed to vote in return for food

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