Shackled, blinded and bound, 30 Al Qaeda and Taliban detainees stepped off a U.S. Air Force C-141 cargo plane in Guantanamo Bay, Cuba, Wednesday after an all-night flight from Afghanistan, halfway around the world.

Sixty gun-toting Marines met the group, bracketing each prisoner and gripping him by the shoulders as the group was led to waiting school buses to be taken to the open-air cages where they would be held until a permanent facility is finished.

Another 30 detainees were on their way from Kandahar were due to arrive Thursday, boosting the total inmate population to about 110.

During the transfer, the Marines removed the blacked-out goggles that had blocked the prisoners' vision since the plane took off from the American air base at Kandahar.

"These are not nice people," said Marine Brig. Gen. Michael Lehnert at a news conference on the U.S. Navy base, America's oldest overseas military facility. "Several have publicly stated here their intent to kill an American before they leave Guantanamo Bay. We will not give them that satisfaction."

Nonetheless, murmurs that the United States was treating the detainees less than humanely continued to be heard, with a top United Nations official Wednesday joining Amnesty International in voicing concern. Lehnert said an International Red Cross team would inspect the camp Thursday.

Lehnert said none of the prisoners had yet been interrogated at the temporary detention center, known as Camp X-Ray. He added that they were not being allowed legal representation, and did not say if and when they would be.

"They spend their days praying, meditating, eating," said Lehnert, commander of a task force overseeing the operation in Guantanamo Bay.

Camp X-Ray can currently hold about 200 inmates, but will be expanded to a capacity of over 600 as builders finish a permanent facility elsewhere on the sprawling Navy base that will be able to hold 2,000 prisoners.

The United States is holding more than 400 prisoners at Kandahar airport in southern Afghanistan. Ninety prisoners of Pakistani origin will be transferred to Pakistan, said Gen. Richard Myers, chairman of the Joint Chiefs of Staff.

None of the detainees has been identified by U.S. officials. A Saudi Interior Ministry official said Wednesday that some Saudis captured in Afghanistan were transferred to Guantanamo Bay, and British officials have said three Britons are among the prisoners there.

The prisoners will eventually face intense interrogation, especially concerning the whereabouts of accused terrorist Usama bin Laden, the prime suspect in the Sept. 11 terror attacks.

The London-based rights group Amnesty International has said the plan to house detainees in "cages" would "fall below minimum standards for humane treatment," and that the temporary cells — 6 feet by 8 feet — are smaller than "that considered acceptable under U.S. standards for ordinary prisoners."

Mary Robinson, U.N. High Commissioner for Human Rights, on Wednesday urged respect for the prisoners' human rights.

White House Press Secretary Ari Fleischer said President Bush was satisfied with the prisoners' treatment.

"It is humane; it is respectful," Fleischer said. "The president is satisfied that they are being treated as Americans would want people to be treated."

The United States is reserving the right to try Al Qaeda and Taliban captives on its own terms and is not calling them "prisoners of war," a designation that would invoke the Geneva Convention.

The Geneva Convention, which has been revised several times since first being drafted by the Red Cross in 1864, is clearest when applying to uniformed members of a sovereign nation's armed forces, and gives them definite rights when taken prisoner during wartime.

The United States maintains that members of the Taliban militia, civilian-garbed fighters for an unrecognized government, do not fall within the convention's statutes. It sees Al Qaeda members as part of a criminal terrorist organization.

But the 1949 revision of the convention extends prisoner-of-war status to "militias or volunteer corps," which might be interpreted to apply to the Taliban detainees, provided it can be shown that they "conduct[ed] their operations in accordance with the laws and customs of war."

British Prime Minister Tony Blair said the prisoners should be treated fairly, in keeping with international rules. Blair said they were being given exercise, showers, medical treatment, copies of the Koran and time for Muslim religious observance.

"There should be no doubt, firstly, that we are dealing with very dangerous people and secondly, however, we are a civilized people and we will treat prisoners in a proper and humane way," he said.

Fox News' Paul Wagenseil and the Associated Press contributed to this report.