Customers of DBS Bank and POSB were unable to access several banking services for up to five hours yesterday.
From about 10am, many users reported not being able to withdraw cash from ATMs, access online banking or pay using their debit cards.
A spokesman for DBS - which also owns POSB - confirmed the disruption in a statement yesterday afternoon and said a "small number" of ATMs and some online banking services were "intermittently impacted by a connectivity issue" - though she could not explain further.
She also said customers may have "experienced issues" using their cards, adding that the bank is investigating and there had been no complaints from overseas users.
Telco analyst Clement Teo of research firm Forrester suggested that there could have been a problem with the communication link between bank branches and the central server. He added: "Card payments could also be affected if the points of sale were not able to get a response from the central server to verify the customer's identity."
The bank, which has more than 1,100 ATMs and over four million customers in Singapore, would not say how many machines or users were affected.
ATMs in areas including Orchard, Raffles Place, Woodlands, Yishun, Toa Payoh and Serangoon were reported by customers to be affected.
The spokesman said all services were fully restored by about 3pm, adding that customers' accounts "remain secure".
Freelance events manager Anastasia Kuznetsova, 27, had trouble paying for her groceries with her DBS debit card at the FairPrice outlet at Serangoon's nex mall around 1pm.
"I tried paying by both Nets and Visa but it didn't work," she said. "Then I tried using the POSB ATM outside but it was not working either. Everyone around me had the same problem too."
A POSB sales executive at Toa Payoh's HDB Hub said that he could not check customer records between 10am and 2.15pm as the system was down.
Customers complained about the issue on DBS and POSB's Facebook and Twitter pages.
Last October, users could not withdraw money from DBS, UOB and OCBC ATMs after a fire broke out at SingTel's Internet exchange in Bukit Panjang. A week later, DBS and POSB customers had trouble using some DBS ATMs for half an hour, which the bank attributed to a "system connectivity issue".
This article was first published on June 17, 2014.
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