An attorney for a Guantanamo Bay detainee has asked a judge to block a planned medical procedure on the prisoner's heart, saying it puts his life at risk if performed at the base.

Saifullah A. Paracha, a 69-year-old multimillionaire businessman from Karachi, Pakistan, already had one heart attack while in U.S. custody and in recent days has suffered chest pains, his lawyers said. Doctors plan to perform a cardiac catheterization on Paracha this month at the isolated Guantanamo Bay Naval Base in southeast Cuba.

Gaillard T. Hunt, one of Paracha's attorneys, asked a federal court in Washington Tuesday to block it, saying Guantanamo lacks the medical facilities for the procedure and sufficient backup in case anything goes wrong.

"There is no excuse for risking petitioner Paracha's life by subjecting him to this procedure at Guantanamo," Hunt said in an emergency petition, a copy of which was provided to The Associated Press.

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Transferring Paracha to a hospital in the United States could present legal complications for the Bush administration, which has maintained that because the Guantanamo detainees were picked up overseas and are being held on foreign land, they may be detained indefinitely without charges or trial.

Paracha's legal team has no ulterior motives, said another of his lawyers, Zachary Philip Katznelson.

"Our goal here is not anything duplicitous or underhanded to get court jurisdiction," he said in a telephone interview. "It is to get decent medical care."

Katznelson said he found Paracha chained to a bed at the base hospital when he visited Guantanamo on Nov. 7 and 9.

"All four limbs were shackled to the bed," and there wasn't enough slack in the chains to enable Paracha to turn over, he complained.

During a cardiac catheterization, a doctor inserts a thin plastic tube into an artery or vein in the arm or leg and pushes it into the chambers of the heart or into the coronary arteries to measure blood pressure within the heart and blood oxygen levels.

Hunt said it should be carried out in a hospital in the United States or Pakistan.

But Army Lt. Col. Lora Tucker said from Guantanamo that its medical facilities "are excellent" and that additional specialists and medical equipment could be brought to the U.S. Navy base as needed.

"We are committed to preserving the health and lives of all detainees," Tucker said in an e-mail to AP. She declined to discuss Paracha because it is against policy to discuss a specific detainee's heath.

There have been three deaths among detainees at Guantanamo since it began taking in men captured in Afghanistan and other areas in January 2002 — all suicides on June 10. Some 430 men are currently held at the prison camp.

On Nov. 7, Paracha suffered chest pains at Guantanamo and a medical technician was brought in, Katznelson said in a statement to the court.

Paracha's pulse had dropped to 46 beats per minute and his blood pressure was around 90 over 58 — serious danger signs, according to Dr. Donald E. Brandon, a doctor in New York City.

"It is sufficient for circulation, but it sounds like he has serious heart disease and is on the verge of another heart attack," Brandon, who has no personal knowledge of the case, said in a telephone interview.

Paracha suffered his first heart attack in 1995 and had a second one in 2003 while in U.S. military custody at Bagram Air Base in Afghanistan, Katznelson said. His family in Pakistan, concerned about his health, has urged Pakistan's government to seek his return home for treatment.

A computer science graduate of the New York Institute of Technology, Paracha was arrested on arrival in Bangkok, Thailand, in July 2003, held in isolation for 14 months in Afghanistan and then sent to Guantanamo.

Paracha has acknowledged meeting Usama bin Laden twice, but denied making investments for Al Qaeda members, translating statements for bin Laden, joining in a plot to smuggle explosives into the United States or recommending that nuclear weapons be used against U.S. soldiers.