Acting on a tip, immigration police at the airport on the island of Samui searched Alain Bellaiche, 40, after he arrived Sunday on a flight from Bangkok, and determined that he was carrying the drug in 65 small packets that he had swallowed in an attempt to avoid detection, said Police Capt. Narongpol Pilmolsiri.
Narongpol said the suspect told police he had swallowed the drug while in Sao Paulo, Brazil, before flying from there to Bangkok and taking a connecting flight to Samui, which is in the Gulf of Thailand about 410 kilometers (290 miles) south of Bangkok.
X-rays showed several capsules in Bellaiche's stomach, and police took him to a hospital where he took a laxative to help him excrete the packets, Narongpol said.
Police said Bellaiche, whose hometown they were unable to provide, was in custody pending further investigation. He could face life in prison if charged and convicted of drug trafficking, police said.
Cocaine is mostly used in Thailand by the wealthy. Methamphetamine and heroin - both produced in the region - more popular among the less affluent.