He may be aged, isolated and facing economic ruin, but Robert Mugabe still clings to power thanks to a feared state security apparatus that continues to function across Zimbabwe.

As the 84-year-old leader marked nearly three decades in power yesterday with a defiant speech against Britain, the Africa correspondent of The Times recalled, just 48 hours after his release from jail, his experiences of Mr Mugabe’s ruthless regime.

Jonathan Clayton spent eight days imprisoned in Bulawayo, Zimbabwe’s second city, where he was interrogated, beaten and tortured by a senior officer in the feared Central Intelligence Organisation (CIO). He was eventually released after paying a Z$20 billion fine, about £200, for misleading an immigration officer.

During his incarceration in various prisons, he found generosity and humanity from officers and inmates alike. But he also endured brutality at the hands of a local intelligence chief, nicknamed “Mr Nasty”, who led a team of a dozen security officers during a five-hour interrogation session at a secret location near the city centre.

The experience, which other prisoners had also endured, revealed that even in provincial areas far from Harare, Mr Mugabe’s writ is still respected and his security operation keeps tight control over society.

But he also discovered that other parts of the security services were showing signs of strain. Several of his fellow cellmates were police officers and soldiers arrested for desertion. Many of the others were desperate young men, convicted of stealing in order to survive. While the prisons were full, there was no food or drink for inmates. These were provided by Christian charities. Yesterday Mr Mugabe marked the country’s 28th independence anniversary by attacking Zimbabwe’s former colonial ruler. “Down with Britain. Down with the thieves who want to steal our country,” said the former guerrilla leader, warming to a familiar theme of blaming the country’s ills on Britain.

“Today they have perfected their tactics to a more subtle form by using money to buy some people to turn against their government. We are being bought like livestock,” he said.

Some 15,000 Zanu (PF) loyalists and a guard of honour turned out to salute Mr Mugabe, as he made his first major public speech three weeks after presidential elections, whose results have still not be revealed by the electoral commission.

In spite of the pomp, the anniversary marked a low point in Zimbabwe’s international standing, where there is a growing outcry over the election failure and the subsequent violent crack-down on the opposition Movement for Democratic Change (MDC), which claims it won the presidential and parliamentary votes. Two MDC members have been killed and dozens injured by pro-Government vigilante groups.

One clear sign that Zimbabwe is losing its support abroad came from Durban, where South African dockers refused to unload a freighter carrying Chinese weapons bound for Zimbabwe’s armed forces.

“We do not believe it wil be in the interest of the Zimbabwean people in general if South Africa is seen to be a conduit of arms and ammunition,” Randall Howard, a transport union spokesman, said. The move could herald the broadening on an international arms boycott against Harare.

As one of Mr Clayton’s cellmates observed about his country’s leader: “The last kick of the dying horse is the hardest.”

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