Japanese banks that lost some 1.8 billion yen ($16.5 million) when fake overseas cards were used at convenience store ATMs are scrambling to combat such fraud.
Seven Bank, which operates ATMs in the 7-Eleven convenience store chain, halved its withdrawal limit to 50,000 yen from 100,000 yen for customers using non-Japanese cards.
E-net, a joint-banking service whose members include national and regional banks, reduced its withdrawal limit to 40,000 yen from the previous 200,000 yen for non-Japanese cards.
The illegal withdrawals were made using fake cards of a South African bank in just a few hours on May 15 at more than 1,000 ATMs in 17 prefectures (states), according to Japanese media reports.
Police have arrested three suspects so far, one in Tokyo and two in Aichi prefecture in central Japan. In the latest development, police found a manual with detailed instructions on how to use fake cards to withdraw money from ATMs, national broadcaster NHK reported yesterday.
Masatoshi Ogihara, a Seven Bank spokesman, said the bank is strengthening monitoring and cooperation with police but declined to provide specifics for security reasons.
China Union Pay cardholders used to be able to withdraw up to 200,000 yen at Seven Bank, Ogihara said, but are also now limited to 50,000 yen.
Money was also taken at Japan Post Bank ATMs. Hayato Kayanuma, a spokesman for the postal bank, said it is working on plans to deal with the fraud but has not lowered the withdrawal limit. He added that the plans would not affect cards issued in Japan.