WASHINGTON (CNN) -- The chief of Amnesty International USA alleged Sunday that the Guantanamo Bay detention camp is part of a worldwide network of U.S. jails, some of them secret, where prisoners are mistreated and even killed.

William Schulz, executive director of Amnesty's Washington-based branch, speaking on "Fox News Sunday," defended the human rights group's recent criticism of U.S. treatment of detainees at the naval base in Guantanamo Bay, Cuba.

"The U.S. is maintaining an archipelago of prisons around the world, many of them secret prisons, into which people are being literally disappeared, held in indefinite, incommunicado detention without access to lawyers or a judicial system or to their families," Schulz said.

"And in some cases, at least, we know they are being mistreated, abused, tortured and even killed."

Schulz's comments were the latest in a volley of incriminations and denials between Amnesty and the White House.

London, England-based Amnesty International's report, released May 25, cited "growing evidence of U.S. war crimes" and labeled the U.S. detention facility at Guantanamo Bay as "the gulag of our times." (Full story)

U.S. officials responded with outrage. Defense Secretary Donald Rumsfeld rebuffed such a comparison, saying a gulag was where the Soviets "kept millions in forced labor concentration camps." (Full story)

President Bush said the comparison was "absurd" and Vice President Dick Cheney said he was offended by Amnesty's assertions. (Full story)

Schulz also answered questions about previous remarks in which he labeled Rumsfeld and Attorney General Alberto Gonzales as "alleged high-level architects of torture."

"Any nation that is party to the Geneva Conventions ... is obligated under international law to investigate those who are alleged to be involved with the formulation of a policy of torture or with its carrying out," Schulz said.

He went on: "The United States should be the one that should investigate those who are alleged at least to be architects of torture, not just the foot solders who may have inflicted the torture directly, but those who authorized it or encouraged it or provided rationales for it." Senators weigh in

A high-ranking Republican senator said Sunday that hearings on abuse allegations at Guantanamo Bay might be appropriate, and a top Democratic senator suggested closing down the prison.

"Look, it's very difficult to run a perfect prison," Majority Whip Mitch McConnell of Kentucky said on CNN's "Late Edition."

"But we have an open country. We have hearings on a whole lot of different subjects. We might well have hearings on this."

Sen. Joseph Biden of Delaware, the ranking Democrat on the Senate Foreign Relations Committee, said he thinks the Guantanamo Bay prison imperils the nation and should cease operating.

"This has become the greatest propaganda tool that exists for recruiting of terrorists around the world, and it is unnecessary to be in that position," Biden said on ABC's "This Week."

He called for an independent commission to review operations at Guantanamo and other U.S. military-run prisons and make recommendations to Congress.

"But the end result is, I think we should end up shutting it down," Biden said.

McConnell, the Senate's No. 2 Republican, objected to some of the language used by critics of the prison -- particularly Amnesty's gulag comparison.

"There is no country in the world that has stood for human rights more than the United States," McConnell said.

"Does that mean that a given soldier in a given situation may have made mistakes? I think some were made at Abu Ghraib, maybe some were made in Guantanamo. Our people are not perfect."

Other human rights groups have criticized activities at Guantanamo Bay, a station the United States has leased from Cuba since 1903.

In a 2004 report, the Red Cross called the psychological and physical coercion used at Guantanamo Bay "tantamount to torture."

Human Rights Watch said U.S. interrogators had inflicted religious humiliation on Muslim detainees, a violation of the Geneva Conventions.

The U.S. military issued a report Friday that detailed four incidents where camp personnel mishandled the Quran at Guantanamo Bay, which holds about 540 detainees. (Full story)

The report concluded that inmates -- not U.S. military personnel as previous reports claimed -- tried to flush the book down a toilet. The report was issued by Brig. Gen. Jay Hood, commander of the detention center.

The incidents included guards kicking a detainee's Quran; a guard stepping on a detainee's Quran; a guard's urine going through an air vent and splashing a detainee and his holy book; and a guard water balloon fight causing two detainees' Qurans to get wet.

In a fifth confirmed incident, it could not be determined whether a guard or a detainee wrote a two-word obscenity in a detainee's Quran.

White House press secretary Scott McClellan insisted Saturday the incidents were "isolated" and did not reflect the behavior of the majority of soldiers.

The investigation was prompted by a Newsweek article citing unnamed sources who claimed U.S. personnel had flushed a Quran down a toilet in an attempt at intimidation. Newsweek later retracted the story.

Commentary:
The land of the free has secret jails, engages in rape, murder and torture of innocent POW's , goes to war for no reason and yet we still some people who follow Bush? My god what does it take for these people to wake up?