Japanese banks were hit on Monday by failures in the nation-wide system that had just integrated online networks of automated teller machines (ATMs) earlier this month.
NTT Data Corp, Japan's largest domestic system integrator, said all types of financial institutions that had their ATMs linked to the nation-wide system were affected.
Systems at about 130 institutions - including the nation's top seven banking groups but excluding insurers and securities firms - were integrated under the network developed by NTT Data.
The failures were fixed around 4 pm (0700 GMT) but the cause of the problem has not been identified, an NTT Data spokesman said.
The spokesman said this was the first failure since online ATM networks, which had differed by the type of bank, were integrated into one system that went into operation on January 5.
Bank of Tokyo-Mitsubishi (BTM), a core unit of megabank Mitsubishi Tokyo Financial Group, said ATM transactions involving other banks were not working properly.
BTM said customers using the bank's cash cards at its own ATMs were not affected. Officials at other banks also noted similar cases.
Resona Holdings Inc, Japan's fifth-largest banking group, said earlier on Monday that about half of the computer terminals located at teller windows at two of its retail bank units and some of its ATMs were not working properly.
Computers were not working properly at branches that formerly belonged to Asahi Bank, which merged with Daiwa Bank to form Resona, and branches of Saitama Resona Bank, Resona said.