A U.N. human rights team said Monday that the Sudanese government has orchestrated crimes against humanity in Darfur, and that steps taken by the international community "have proven inadequate and ineffective."

The team, headed by Nobel peace laureate Jody Williams, urged stronger U.N. Security Council intervention, sanctions and criminal prosecution.

"All U.N. Security Council and [African Union] Peace and Security Council resolutions should be fully implemented, including those relating to travel bans and the freezing of funds, assets, and economic resources of those who commit violations," the 35-page report said.

Important steps have been taken by the international community, including the African Union and the United Nations, but "these have been largely resisted and obstructed, and have proven inadequate and ineffective," the report said.

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More than 200,000 people have died and more than 2.5 million people have been displaced in four years of fighting in Darfur. The conflict began when members of the region's ethnic African tribes took up arms against what they saw as decades of neglect and discrimination by the Arab-dominated government in Khartoum.

The government is accused of unleashing a pro-government Arab militia that has committed many of the atrocities in the conflict.

The U.N. Human Rights Council commissioned Monday's report in an emergency session last December. Williams filed the report after concluding in a 20-day attempt to enter Sudan in February that the Sudanese government had no intention of cooperating with the United Nations.

Sudan's government "has manifestly failed to protect the population of Darfur from large-scale international crimes, and has itself orchestrated and participated in these crimes," the report said.

Monday's report said rape was widespread across Darfur, but that Sudanese authorities were doing little to prevent it or investigate the crimes.

"Arbitrary arrest and detention in Darfur by government security forces continue," the report said, adding that there had been a wave of arrests of Darfurians in the Sudanese capital, Khartoum, in recent months.

There also have been curbs on free speech and "credible information on torture, inhumane and degrading treatment by national Security and Military Intelligence during attacks and in the treatment of detainees," the report said.

Prosecutors at the International Criminal Court in The Hague, Netherlands, last month linked Sudan's government to atrocities in Darfur, naming a junior minister as a war crimes suspect who helped recruit, arm and bankroll the janjaweed.

Ahmed Muhammed Harun, the former junior interior minister responsible for the western region of Darfur, and a janjaweed militia leader, Ali Mohammed Ali Abd-al-Rahman, also known as Ali Kushayb, are suspected of a total of 51 counts of war crimes and crimes against humanity, according to prosecutor Luis Moreno-Ocampo.

Sudan says it already has set up its own war crimes courts, and does not have to turn over suspects named by the ICC.

The report said anti-government rebels also were to blame for human rights abuses, including the rape and torture of civilians. Much of this violence was related to fighting between different rebel groups and an increase in violent banditry in the largely lawless region, it said.

Although the team was unable to enter Sudan, it held numerous consultations with a wide range of aid agencies working in the region and also was briefed by African Union officials in Addis Ababa, Ethiopia, the report said.

In Chad, the team also spoke to some members of rebel groups, including the Justice and Equality Movement and the secretariat of the National Redemption Front, and to Darfur refugees.

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