A Colombian veterinarian who was extradited to the U.S. in May admitted in federal court to smuggling liquid heroin into the country by surgically implanting it into live puppies.

Per WPIX, Andres Lopez Elorez, 39, pleaded guilty Friday in a Brooklyn court and faces at least 10 years behind bars for his crimes. Officials accused Elorez and his accomplices of sneaking one kilogram of heroin into the country between September 8, 2004, and January 1, 2005. Elorez was arrested in Spain in May 2015 and brought to the States to face charges three years later.

READ More: Veterinarian smuggles heroin in puppies’ stomachs for drug trafficking ring: Cops

“I conspired together with another experienced veterinarian to introduce drugs into the United States of America through surgical acts on dogs,” Elorez said in court, according to the New York Daily News.

The New York Post reports that prosecutors specifically accused him of inserting packs of liquid heroin into the bellies of Labrador puppies. The pups were then flown into JFK in New York City, where they were then cut open to recover the drugs. Authorities said all five dogs died as a result.

Authorities discovered 10 live puppies in 2005 during a raid on a Colombian farm. Three of the 10 rescued dogs succumbed to infection, according to the newspaper. At the time, a Drug Enforcement Administration official called the scheme “one of the most outrageous methods of smuggling” he had ever seen, according to The New York Times.

Sentencing is scheduled for January 17. WPIX reported that the vet faces deportation after serving his prison sentence.

[Featured image: Andres Lopez Elorez/Drug Enforcement Administration]