Thieves suspected of installing a computer programme that got cash machines in Taiwan to churn out more than $2 million (Dh7.34 million) were being hunted by police on Tuesday, officials said.
The masked robbers ransacked more than 30 ATMs at the Taipei-based First Commercial Bank, walking away "with bags packed with cash", the bank said in a statement.
It suggested that a malware programme may have been installed on the ATMs, adding that the suspects stole the money without having to operate the machines directly.
Surveillance images showed "two men wearing face masks and hats walking away with bags packed with cash directly withdrawn from ATMs", First Commercial said in the statement.
At least two suspects were involved -- one Russian man, and another foreign suspect whose nationality remains unknown, according to Taipei police.
"It is still not clear how the suspects stole such a large amount of money from the ATMs. My understanding is this is the first time such a criminal method has been discovered here," an officer told AFP.
It took the duo five to 10 minutes to steal money from each of the 34 ATMs over the weekend, the bank said, adding that the theft spanned machines at 20 branches.
It said more than 400 of its ATMs of the same type had been shut down following the heist, which cost the bank T$70 million (US$2.2 million).
Police said the Russian suspect escaped Taiwan on Sunday, adding that they had sought assistance from Interpol.
"ATM crimes were not uncommon, most of them using fake cards or cheating people out of their money using their debit or credit cards on ATMs," the officer said.
More than 700 other cash machines of the same type operated by six other banks have also been shut down.