Thirty-four more detainees from the Afghan war were flown Monday to this remote U.S. military base, where investigators are struggling to pin down which captives fought for the Taliban and which belonged to Al Qaeda.

Civilian and military investigators have been questioning prisoners since Jan. 23, when there were 158 of them here. Flights bringing more resumed last week after being suspended so that they could concentrate on interrogations, and the new arrivals brought the number to 254.

Eight of the new arrivals had to be put into increased security postures shortly after they arrived but there were no major incidents, U.S. Marine Corps Public Affairs officer Maj. Stephen Cox said.

The men normally stand with their feet and hands shackled. The increased security posture forces the detainees onto their sides with their knees to their chests.

There was no specific word on what prompted the extra security moves, but Cox said talking or not responding to orders after three tries can prompt officials to force the position.

Despite three weeks of questioning, U.S. officials have not identified many of the detainees as either Taliban or Al Qaeda members.

"We have more people in limbo," Cox said Sunday. He would not say whether they made up a majority of the prisoners, but confirmed they outnumbered both those claiming to be Taliban and those determined to be Al Qaeda.

Camp officials say many have been interviewed as many as four times, each time providing a different name and different information. They say that it's premature to assume most prisoners were from Al Qaeda, the terror network led by Usama bin Laden and accused in the Sept. 11 attacks.

The first group of prisoners sent to Guantanamo from Afghanistan "was determined to have the greatest intelligence value because of their positions, their standings in either the Al Qaeda or Taliban," Cox said. "Because of that value, they were determined to be the most dangerous — because of the information they possessed."

On Monday, four Cuban refugees arrived at the U.S. base, apparently apparently swimming, officials said. A clerk at the base's bachelor quarters said four men wearing only soaking wet shorts had turned up there. Cuban refugees who come here generally are repatriated.

After visiting the Camp X-ray detention facility two weeks ago, Republican Sen. James Inhofe of Oklahoma said he did not believe more than 15 percent of the 158 detainees there at the time, or about 24 people, were Afghans.

U.S. officials had said the detainees came from 25 different countries. Cox said Monday that the number increased to 26 on Saturday, when another group of 34 arrived from the airport in Kandahar, Afghanistan — as always, aboard a C-141 military cargo plane.

A senior Pentagon official speaking on condition of anonymity last week said the detainees included about 50 Saudis, 30 Yemenis, 25 Pakistanis, eight Algerians, three Britons and small numbers from Australia, Belgium, Egypt, France, Russia and Sweden.

The official did not mention Afghans, who formed the ousted Taliban regime that harbored Al Qaeda while ruling Afghanistan. While some foreigners fought for the Taliban, the majority were believed to be fighting for Al Qaeda.