Ten puppies, including several Labrador retrievers, were discovered on a farm in a makeshift veterinary clinic in Medellín, Colombia, during a raid about a year ago, said John P. Gilbride, the special agent in charge of the Drug Enforcement Administration’s New York Field Division. He said surgical tools and a table for operations were found in the clinic.
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All of the puppies were rescued, but three later died from infections from incisions, Mr. Gilbride said. A total of about three kilograms of liquid heroin, or about a pound per dog, was implanted in six dogs in packets stitched inside the loose skin of their bellies, Mr. Gilbride said, and the remaining puppies were awaiting operations.

The liquid drug, brown in color, was packed in soft, pliable plastic pouches, some transparent. The veterinarian, identified by one law enforcement official as Andres Lopez Elorez, is a fugitive believed to be in Spain.
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Asked how the drugs would be extracted from the puppies, one law enforcement official, who spoke on the condition of anonymity because the investigation was continuing, said, “I don’t think there was any real indication, but I don’t think they were going to be real careful.”