Serious disruption occurred in online operations and credit card transactions for a number of Turkish banks on 25th of December, reports say.
A series of cyber attacks have been launched by hackers over the past week.
Officials at several Turkish banks including Iş Bank, Garanti and state lender Ziraat Bank confirmed the attacks, saying they had caused intermittent disruption, Reuters reported.
Bank shares were not affected by these events.
“The attacks are serious,” said Onur Oz, a spokesman for Internet provider Turk Telekom. “But the target is not Turk Telekom. Instead, banks and public institutions are under heavy attack,” he said.
“A majority of Turkish institutions use Turk Telekom as the service provider, therefore we are the ones defending against these attacks.”
Around 50,000 computers in Turkey unintentionally contributed to attacks without the knowledge of their owners, according to experts who commented on the attacks that intensified on banks for two days.
The technique used by Anonymous, the hacker group alleged to be behind the cyber attack, is known as a Denial of Service Attack (DDoS), experts said.
A DDoS is basically a bid to overrun the user capacity of a website, blocking it due to a high traffic. Hackers use software hidden in thousands of computer to direct such traffic to targeted websites. This technique turns unaware users’ computers into “zombie” machines to carry out the attack.