Tokyo police say the four Japanese men in the Philippines who are suspected of giving instructions in a series of robberies in Japan are members of a group linked to cases of special fraud.

The four now being held at an immigration facility in the Philippines are Watanabe Yuki, Kojima Tomonobu, Fujita Toshiya and Imamura Kiyoto.

The Tokyo Metropolitan Police Department had earlier obtained warrants for their arrest on suspicion of involvement in special fraud. It plans to send officers to the Philippines to prepare for their handover.

The police suspect three of them were involved in stealing two cash cards from a man in Tokyo in 2019 after falsely telling him by phone that balance inquiries were being made to his account illegally.

Investigators say the four men are members of a group that made such calls to Japan from the Philippines.

The police estimate that the group has been linked to about 2,300 fraud cases, with damage of around 3.5 billion yen, or about 27 million dollars.

More than 70 members of the group have been caught so far.

Investigators say Watanabe is believed to be the ringleader of the group.