Amnesty's call came as Mugabe and his opposition are deadlocked over a unity government deal that could see Mugabe yield some power for the first time in the nearly three decades he has led Zimbabwe. Some fear the stalled deal could collapse because Mugabe's supporters and perhaps Mugabe himself fear they will face human rights trials if his absolute power is undermined.

But the international human rights group said accountability was key.

"If the perpetrators are allowed to roam ... they will do it again," Simeon Mawanza, Amnesty's Zimbabwe researcher, said at a news conference in South Africa on Friday.

In a report released at the news conference, Amnesty said the Mugabe "government's deliberate policy of protecting those who have committed human rights violations in order to maintain its hold on power has allow human rights violations to escalate."

The report included witness accounts of abuses starting in 2000, when the opposition Movement for Democratic Change first proved itself a real challenge to Mugabe's ZANU-PF party.

Mugabe has repeatedly denied such accusations. But in the power-sharing agreement he signed Sept. 15, he acknowledged "the easy resort to violence by political parties, state actors, non-state actors and others in order to resolve political differences and achieve political ends."

The yet-to-be-implemented September agreement _ also signed by main opposition leader Morgan Tsvangirai _ pledges that the unity government would "apply the laws of the country fully and impartially in bringing all perpetrators of politically motivated violence" to justice.

Repeated attempts to reach Zimbabwean government and police officials for comment were not immediately successful. Tsvangirai's spokesman, Nelson Chamisa, said he could not comment before studying the report.

Tsvangirai has called for truth and reconciliation hearings to address his nation's history of political violence. Tsvangirai has said trials could distract from the work of rebuilding Zimbabwe. But earlier this month, addressing a rally in a northern area believed to have seen some of the worst attacks, he said: "Justice must not only be seen to be done, but it should be done." He did not elaborate.

Amnesty called on Zimbabwe to form an independent commission to investigate human rights violations.

Tsvangirai's party came close to winning a disputed parliamentary election. This year, Mugabe is accused of unleashing so much violence after a March vote that Tsvangirai withdrew from a June runoff. Mugabe claimed victory in the runoff, but it was widely denounced as a sham.

Amnesty singled out the police force, accusing its members of torturing detainees and using excessive violence to quell protests, in at least one case resulting in the death of a demonstrator.

"The Zimbabwe Republic Police ... is the main institution responsible for serious human rights violations," Amnesty said.

Tsvangirai has insisted on taking over the police ministry, while Mugabe has refused to yield it.

Without a deal, Zimbabwe is left without leadership as its economy collapses.

Roads, power and water services, schools and hospitals are deteriorating. Food, gasoline and medicine are scarce, and even if Zimbabweans could find goods in the stores, they could afford to buy little with official inflation of 231 million percent _ the highest in the world. The U.N. predicts at least 5 million people, half of the population, will need food aid by January. - (AP)