PARIS — The prosecutor at the International Criminal Court on Monday formally requested an arrest warrant for President Omar Hassan al-Bashir of Sudan on charges of genocide and crimes against humanity committed during the last five years of bloodshed in his country's Darfur region.
Announcing the request, the prosecutor, Luis Moreno-Ocampo, said that Bashir "masterminded and implemented" a plan to destroy the three main ethnic groups in Darfur, the Fur, Masalit and Zaghawa.
"His motives were largely political," the prosecutor said. "His alibi was a counterinsurgency. His intent was genocide." Moreno-Ocampo, of Argentina, charged that, having failed to defeat a rebellion, the Sudanese president turned against civilians. "Al-Bashir organized the destitution, insecurity and harassment of the survivors," he said. "He did not need bullets. He used other weapons: rapes, hunger and fear. As efficient, but silent."
At a news conference at the court in The Hague in the Netherlands, he said that he handed over his evidence on Monday morning to the three judges who will decide whether to issue an arrest warrant. An answer to the request is expected in the autumn, lawyers at the court said.
Genocide charges are the gravest any court can bring, and the prosecutor is expected to implicate others at the top of the Sudanese government.
The action against Bashir marks the first time the International Criminal Court has brought any charges against a sitting head of state since it opened its doors in 2002. Two other presidents, Slobodan Milosevic of Serbia and Charles Taylor of Liberia, were both charged by other international war crimes courts while in office.
But the request for a warrant against Bashir, whose regime has repeatedly ignored international requests to stop attacking civilians, seemed unlikely to lead to his arrest in the short term.
Bashir has scoffed at two arrest warrants the court has already issued against two other Sudanese officials, even promoting one of them to minister of humanitarian affairs.
The government of Sudan immediately rejected the accusations and said it would fight the charges through legal means.
"We will resist this," said Rabie Atti, a Sudanese government spokesman. "Everybody in Sudan - the government, the people, even the opposition parties - are against this." He said that Bashir was innocent and that the international court was "a stooge" for Sudan's enemies.
He added that the government was appointing a team of African and Arab lawyers to handle the case.
He also said that the government would not vent its outrage on the thousands of United Nations and African Union peacekeepers in Sudan or aid workers.
"Nothing will happen to the UN because of this," he said. "We will handle this with our legal advocates."
A key question is whether the United Nations Security Council will intervene in this case. The council itself in 2005 asked the court to investigate the Darfur crisis, but it has the authority to suspend an investigation or prosecution for a one-year period. Since the prosecutor notified the UN secretary general, Ban Ki Mmoon, last week of his plan to bring charges against Bashir, council members have met privately, with China and Russia warning that a direct move against the Sudanese president would jeopardize any future peace talks.
In Sudan, UN aid workers and peacekeepers, worried that the announcement of the warrant could hinder their work and prompt reprisals against their personnel, stepped up security in Darfur, pulling out all but the most essential civilians. Other aid organizations have temporarily evacuated some of their staff from Darfur to Khartoum.
Peacekeepers in the region, part of a hybrid United Nations and African Union force, are particularly vulnerable, diplomats and analysts say. The Sudanese government resisted merging a weak and under-equipped African Union mission with a United Nations force, arguing that UN troops would simply be used to execute arrest warrants for the international court.
Many Arab leaders in Darfur supported the government's refusal to accept UN troops for the same reason, given that the war crimes charges that have arisen thus far involve Arab militias in Darfur. Seven peacekeepers were killed in an ambush last week, and the force has been struggling to simply protect itself.
In the vast, restive camps of displaced people in Darfur, demonstrations in support of the international court are likely. Julie Flint, an independent researcher who has written extensively about Darfur, said that such demonstrations would likely provoke a harsh response from Sudanese security forces.
"The camps are my biggest worry," Flint said. "They could explode into violence." Even if the government of Sudan did not react immediately to the announcement, it could make life harder for the displaced of Darfur and the people trying to help them "in a thousand ways," Flint said. "They can slow down permits. Make visas impossible to get. They can make an already difficult job impossible."
The government has made no secret of its desire to see displaced people in Darfur leave the sprawling camps that are home to 2 million of people whose villages were attacked in the conflict.
"There is a great deal of concern that the camps will be vulnerable in this period," said a senior aid official in Sudan, speaking anonymously to avoid retribution. "The government has been looking for a reason to shut them down."
Marlise Simons reported from Paris and Lydia Polgreen from Dakar, Senegal. Alan Cowell contributed reporting from London and Jeffrey Gettleman from Nairobi.