GUANTANAMO BAY, Cuba - Military officials say that prisoners at the detention center here have provided a steady stream of valuable intelligence to interrogators during the past two years, including information about al-Qaida's use of charities as false fund-raising fronts and about the recruitment of Muslim men in Europe.
In interviews during an arranged tour, military and intelligence officials asserted that detainees who had been cooperating with interrogators had also provided information about al-Qaida's chemical and biological weapons efforts and how the group trains suicide bombers.
"We have been able as a result of information gained here to take operational actions, even military campaigns," said Steve Rodriguez, a veteran intelligence officer who oversees the interrogation teams - which operate 24 hours a day here. "There are instances of learning about active cells, and we have taken action to see that the cell was broken."
The sweeping set of official assertions about the value of the detention center at Guantanamo is part of an overall effort by the Bush administration to counter increasing criticism here and abroad about the operation, along with new allegations of mistreatment of prisoners here.
Another U.S. official said that analysts had been able to attain an understanding of a kind of underground network in Europe in which young Muslims are selected and then drawn into al-Qaida by imams and Islamic cultural centers and eventually sent to Afghanistan.
Efforts in Europe to counter al-Qaida have taken on urgency since the Madrid, Spain, bombings March 11.
Rodriguez said that despite the fact that some of the detainees had been at Guantanamo for nearly two years, their information was still useful. "I thought that when I first came here there would be little to gain," he said. "But when they talk about what happens in certain operational theaters, the locations of certain pathways, that information doesn't perish."
The first military tribunals for some prisoners might occur as early as summer, which is expected to engender new criticism. In addition to the many challenges to the legal basis the United States has noted to justify the detentions, several recently released prisoners have provided accounts to journalists of mistreatment ranging from enforced privation and petty cruelty to beatings and planned humiliations.
In an apparent effort to counter that criticism, officials offered to talk in far greater detail than they had previously about their interrogation techniques and what they say are important intelligence harvests from the detainees. The officials also denied the specific allegations of mistreatment made by prisoners recently returned to Britain whose accounts appeared in British newspapers and from Afghans who spoke to The New York Times in Kabul.
However, there is no way to verify independently the situation as described by the U.S. officials, just as the recent accounts by the former prisoners of mistreatment cannot be confirmed independently.
Rodriguez said a large number of the 610 detainees had not been cooperative with their interrogators. He said at least 50 were "ardent jihadists and have no qualms about telling you that if they got out they would go and kill more Americans."
Rodriguez's emphasis on the most hard-core detainees raises one of the significant questions about Guantanamo: Does the prison camp also house large numbers of innocent men who were swept up in the chaotic aftermath of the Afghanistan war? Human rights groups and family members of those who have been detained have said that the United States has committed a gross injustice by imprisoning many people who were in Afghanistan or Pakistan for reasons other than to join the Taliban or fight with al-Qaida. More than 100 prisoners from Guantanamo have been released.
Three former British prisoners who are friends from the city of Tipton said in interviews published this month in The Sunday Observer that they were arrested after they had gone to the region to arrange a marriage for one of the men. One of the other men was to serve as best man. They spoke of beatings and abuse by U.S. soldiers.
Maj. Gen. Geoffrey Miller, the departing commander of the Joint Task Force, which runs the prison camp at Guantanamo, denied the allegations.
He also said he was confident that all the men there had been properly screened and fit the definition of an enemy combatant. "These people have a number of cover stories," he said. "I can say with certainty that the British detainees were here for an appropriate reason."
Rodriguez said, "If I were to believe the stories they tell me at first, then 90 percent of them are innocent rug merchants."