Thousands crammed a soccer stadium near Zimbabwe's eastern Mutare city, their cheers rising to a deafening roar as the country's only effective opposition leader made a triumphant entrance in an open-topped vehicle.

Club-wielding police refrained from breaking up the weekend rally. But Human Rights Watch, in a report released Monday, says years of violence, intimidation and repression already have skewed this month's parliamentary vote in favor of the country's aging and embattled President Robert Mugabe.

As a result, the March 31 elections are "highly unlikely" to reflect the free expression of voters, the New York-based rights groups says.

"The government has denied the opposition, civil society activists and ordinary citizens the right to freely express their opinions," Human Rights Watch researcher Tiseke Kasambala said at a news briefing in Johannesburg.

Calls to Mugabe's information department in Zimbabwe seeking comment went unanswered Monday.

Facing accusations that his nearly 25-year rule has descended into tyranny, Mugabe has promised the vote will be peaceful and has enacted electoral reforms he says bring the country in line with regional standards.

In January, Secretary of State Condoleezza Rice branded Zimbabwe one of the world's "outposts of tyranny."

When opposition leader Morgan Tsvangirai campaigned in Mutare during presidential elections three years ago, his Movement for Democratic Change said ruling party supporters threatened to "punish" anyone who attended.

On Saturday, police kept a discreet distance as Tsvangirai accused the government of chasing away foreign aid groups and failing to feed the population stricken by drought, AIDS and a calamitous land redistribution program.

"The problem with this country is that the ones who are eating are the few; the ones who are suffering are the majority," Tsvangirai said.

While opposition officials and their suspected supporters are still threatened and beaten, the level of violence has declined markedly since the last legislative poll in 2000.

That vote was closely followed by the often bloody — and sometimes deadly — seizure of thousands of white-owned farms for redistribution to blacks.

Kasambala said the government no longer needs overt violence to persuade voters to cast ballots for the ruling Zimbabwe African National Union-Patriotic Front — or not vote at all.

The 35-page Human Rights Watch report documents numerous incidents of political intimidation.

Traditional chiefs have been asked to compile lists of potential opposition supporters, and voters in desperately hungry rural areas have been told they could forfeit food aid if they don't vote for the ruling party, Kasambala said.

Mugabe's government has also expanded its legal arsenal to restrict the activities of political parties and civil society activists.

Police have repeatedly used the Public Order and Security Act, introduced after Mugabe's party narrowly won the 2000 poll, to ban opposition meetings and arrest those critical of the government, political and rights activists said.

The Access to Information and Protection of Privacy Act, which followed closely fought presidential polls in 2002, has been used to shut down a number of independent newspapers and arrest their journalists.

Police, courts and civil service have been restructured with government loyalists at the helm, the report said. Training centers for the ruling party's feared youth militia have expanded, and voter education has been curtailed.

A new electoral commission is neither impartial, independent nor inclusive, the report said. And by the time it began to operate in February, many of its functions — including compiling a voters roll opposition leaders say is woefully inaccurate — had already been performed by the same electoral bodies as in previous elections.

The estimated 3.4 million Zimbabweans living abroad — more than 20 percent of the population — have been barred from voting.

Mugabe's government has only invited a select few governments and organizations to monitor the poll, excluding those who concluded previous elections were marred by violence, intimidation and vote-rigging.

Mugabe's party took just 62 of Parliament's elected seats in 2000, but has claimed six others in by-elections. The president appoints an additional 30 seats, virtually guaranteeing his party a majority.

Opposition party officials, however, say the years of political and economic turmoil have created a groundswell of opposition that could yet propel them to power.