SAN DIEGO -- An 81-year-old American cancer patient who says that he traveled to Tijuana, Mexico, to buy Valium to relieve his pain has been arrested and jailed on suspicion of drug smuggling.

George Paul Murl (pictured, left) of Oxnard, Calif. is being held in a state penitentiary in Tijuana after he was arrested outside a pharmacy with 600 Valium pills, U.S. and Mexican authorities said.
Murl was arrested on May 24 because he did not have a legitimate prescription for the pills, said Lorenzo Garibay, a spokesman for the Tijuana police department.
Police turned the case over to federal prosecutors, which is standard in drug cases, Garibay said.
"If you have a prescription it's no problem," he said. "If not, you can be arrested as a drug trafficker."
But an American minister who has visited Murl in prison said that the elderly man did have a prescription and has been buying Valium in Tijuana for several years because it is cheaper than in the United States.
The minister, David Walden of San Diego, said that Murl has prostate cancer and should be released from prison on humanitarian grounds.
"He's sick. He needs medical attention," said Walden, who has carried food and other supplies to American prisoners in the Tijuana penitentiary for six years.
Many Americans Purchase Medications Across BorderTijuana's many pharmacies have long attracted U.S. consumers with lower prices. But arrests for illegally buying certain drugs are fairly common.
Walden said that several of the 48 U.S. citizens currently at the penitentiary were arrested on similar offenses but Murl is the oldest by far.
Though pharmacies in Tijuana often sell prescription drugs over-the-counter, legally consumers must have a prescription from a Mexican doctor, 10News reported.
In most cases, consumers are limited to a 90-day supply.
Americans can bring prescription drugs into the U.S. without a prescription, but are limited to 50 dosage units, according the the U.S. Drug Enforcement Administration.
Any amount over 50 units requires a prescription from a U.S.-licensed physician authorized by the DEA to prescribe the medications.
U.S customs supervisor Virginia Gengor says that with few exceptions, the medicine must be in its original, unopened container.
Many of the pharmacies in Tijuana sell prescription drugs by the pill, dispensed in unsealed containers.
Murl, a World War II veteran, was told that he faces up to five years in prison if convicted, Walden said.
Friends of Murl say that he may be transferred to a Tijuana hospital Thursday, and might be allowed to return to the U.S. next week.
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