Authorities arrested three foreigners at about 2am on Saturday morning on an island off the coast of Sihanoukville on suspicions of trafficking marijuana.

The three foreigners – Kengo Yasu Kawa, 35, who is Japanese, and two French citizens, Pierre-Jean Firmin, 27, and Lauri Berther, 22 – were arrested at a party on Koh Rong Samloem.

“At the time the three were arrested, authorities checked and seized five packs of dried marijuana [300 grams] and other evidence,” said Sun Sophat, deputy provincial police chief in charge of economic and drug crimes. “[The suspects] also did not have passports with them,” he said.

According to Sophat, the provincial court will charge the trio for “possession of an addictive plant with intent to distribute”.

David Harding, an independent drug expert, called it “unwise for foreigners to think they would be excluded from” the country’s ongoing drug war, which kicked off in January. However, he said, the foreigners’ case would likely be treated with a “seriousness [that] is not applied to local people”.