Twenty-two Sri Lankan monks returning from Thailand were arrested on Sunday at the main international airport with 110 kilogrammes (242 pounds) of powerful cannabis, officials said.
A Sri Lanka Customs spokesman said the group, returning home after a four-day holiday in the Thai capital, had Kush -- a potent, plant-based strain of cannabis -- hidden in their luggage.
"Each carried about five kilos of the narcotic concealed within false walls in their luggage," the spokesman said, adding that the monks had been handed over to police.
They were to be taken before a magistrate later on Sunday.
The monks were mostly young students from temples across Sri Lanka and had been on a holiday sponsored by a businessman.
Customs officials said it was the largest single detection of Kush at the South Asian country's main international airport.
A 21-year-old British woman was arrested in May last year with 46 kilogrammes (101 pounds) of the drug at the same airport. She was also travelling to Colombo from Bangkok.
Sri Lankan authorities have also made several detections of large hauls of heroin and other narcotics smuggled in via small fishing boats in recent years.
Agence France-Presse