Protest organizers said those arrested included U.S. Representatives Jim McGovern of Massachusetts, Al Green of Texas, Jim Moran of Virginia and John Olver of Massachusetts - all Democrats. Organizers said Ben Jealous, president of the National Association for the Advancement of Colored People (NAACP), and Martin Luther King III, the son of the slain U.S. civil rights hero, also were arrested.

Clooney, his father Nick and the other anti-Sudan activists ignored three police warnings to leave the embassy grounds and were led away in plastic handcuffs to a waiting van by uniformed members of the Secret Service, a Reuters journalist covering the demonstration said.

"We need humanitarian aid to be allowed into the Sudan before it becomes the worst humanitarian crisis in the world," Clooney told reporters just before his arrest.

"The second thing we are here to ask is for the government in Khartoum to stop randomly killing its own innocent men, women and children. Stop raping them and stop starving them. That's all we ask."

Clooney, who on Wednesday was a guest at the White House banquet in honor of British Prime Minister David Cameron, and several others posted bail and walked free later on Friday.

Sudan has denied U.S. concerns that famine might break out in South Kordofan and Blue Nile states, although there is almost no independent access to the region, making it difficult to assess the humanitarian situation.

Khartoum has also restricted access of the United Nations and foreign aid agencies to the region, although it recently did allow the return of some U.N. international staff.

U.S. CONCERN

The United States has voiced serious concern about the deteriorating conditions in the border region, where Sudanese troops are fighting rebels.

Sudan accuses its newly independent neighbor South Sudan of supporting the rebels but Juba denies the charges.

Clooney, who recently visited the area, told a Senate hearing this week that Sudan's forces were launching repeated attacks on unarmed civilians and preventing aid from reaching a region where U.S. officials say as many as 250,000 people face potentially severe food shortages.

Clooney, a long-time celebrity activist critical of the Khartoum government, had been expected to provoke police into arresting him.

Tom Andrews, president of United to End Genocide, another group involved in the protest, said the United States should raise the heat on Khartoum to stop the violence and allow humanitarian access.

"It is unacceptable and inexcusable that Sudan's President Omar al-Bashir — an international criminal wanted for war crimes and genocide — is getting away with bombing, starving and displacing hundreds of thousands of innocent men, women and children in Sudan's Nuba Mountains and Blue Nile State," Andrews, who was also arrested, said in a statement.

The Sudan Embassy in Washington did not respond to a request for comment.

(Writing by Andrew Quinn; Editing by Ross Colvin and Will Dunham)

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