The immigration bureau in Thailand has detained a group of five Japanese men suspected of running a phone scam targeting elderly people in Japan from a base in a central Thai resort city.

Thai immigration officials told reporters on Wednesday that they searched two sites in the city of Pattaya on Monday, and detained the men in their 20s to 40s.

They said they seized a list containing personal information of about 50,000 people.

Officials suspect the five Japanese made calls to potential victims in Japan, impersonating government officials and making false promises of refunds for past medical expenses.

The officials believe the suspects earned as much as 24 million yen, or about 156,000 dollars, a day by defrauding victims.

The five men are expected to be deported to be handed to the Japanese police.