A resort on a Thai island has sued an American for a negative review on Tripadvisor, the Thai authorities said on Saturday.
He could be sentenced to two years in prison.
There is still domestic tourism in Thailand, where the number of coronavirus infections is relatively small.
Locals and expats mostly head to near-empty resorts, including Koh Chang Island, famous for its sandy beaches and turquoise waters.
But a recent visit to the island's Sea View Resort got Wesley Barnes in trouble after writing unflattering online reviews about his vacation.
"The owner of the Sea View Resort filed a complaint that the defendant posted unfair reviews about his hotel on the Tripadvisor website," Colonel Thanapon Taemsara of Koh Chang Police said to AFP.
He said Barnes was accused of causing "damage to the hotel's reputation".
He is also said to have argued with the staff about not paying corkage for alcohol brought to the hotel.
Barnes, who works in Thailand, was arrested by the immigration police.
He was held briefly and then released on bail.
According to the Tripadvisor review that Barnes posted in July, he came across "unfriendly staff" who "pretended they don't want anyone here."