Defence lawyer James Wong says the High Court found Athiseshan Singaram, a textile company driver, guilty of drug trafficking, which carries a mandatory death penalty in Malaysia.
Officials say Singaram was arrested in July 2008 after arriving at the Kuala Lumpur International Airport from New Delhi with 20 kilograms (44 pounds) of ketamine in his bag.
Wong said Sunday that Singaram claimed the drugs were not his and would appeal the conviction.
Ketamine is an anesthetic used for animals and humans, but its psychedelic side effects make it a popular recreational drug.
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