The generic form of the powerful painkiller OxyContin is already for sale on the black market in Appalachia, even though it is not yet available in all pharmacies.

Dan Smoot, chief detective for an anti-drug task force in eastern Kentucky, said undercover narcotics investigators began buying the generic drug from street-level dealers earlier this week. Investigators suspect a shipment of the drugs was stolen from a storage building in eastern Kentucky.

"It's incredible," Smoot said. "When we first got the pills, we didn't know what they were. They look nothing like the OxyContin we were familiar with."

OxyContin is a long-lasting version of oxycodone, a narcotic considered important therapy for many patients suffering chronic, moderate to severe pain from illnesses such as cancer. The tablet, when swallowed whole, provides 12 hours of relief.

But the drug can produce a quick and potentially lethal high if it is chewed, snorted or injected. It has been linked to more than 100 deaths and bears the government's strongest warning label, which says the drug may be as addictive as morphine.

The Food and Drug Administration has given approval for Teva Pharmaceuticals of North Wales, Pa., and Endo Pharmaceuticals of Chadds Ford, Pa., to sell generic versions of extended-release oxycodone. Teva began marketing an 80- milligram tablet in March, but not all pharmacies in Appalachia are offering the drug for sale. Endo has said it will not market its version until Purdue Pharma, the company that created OxyContin, exhausts its appeals in a federal patent lawsuit.

Law enforcement officials were dreading the official release of the generic version, saying it could increase availability and cut the price of the drug on the black market.

Karen Engle, executive director of the anti-drug task force Operation UNITE, said an investigation is underway to try to determine the origin of the generic drug available illegally in Kentucky.

"We didn't know what type of substance our detectives had purchased at first," she said. "We actually had to call the poison control center to have them identify the substance for us."

Smoot, a retired state police narcotics detective now heading law enforcement for Operation UNITE, said the generic drugs circulating in the mountain region may have come from a stolen shipment intended for pharmacies in the region.

Kentucky State Police Detective Eddie Crum said a drug shipment was taken during an April 29 break-in at a storage facility in Pikeville.

Crum said he was surprised to learn that the generic drugs, which usually are transported in armored cars because of their popularity among drug traffickers, were being stored so carelessly.

"We knew when the FDA approved generic OxyContin that it would end up in the region," Engle said. "But we didn't think it would be here before the pharmacies got it."

Engle said the generic drugs on the black market have been selling about $20 cheaper than the original OxyContin. She said the price will be even lower once the pills become available in all pharmacies.

"We're bracing for it," Engle said. "We're hoping we're not hit as hard with the generic brands as we were with OxyContin."