Several top Czech bank websites came under hacker attack on Wednesday, shutting down their internet banking and other online services.
The online banking websites of Erste Group Bank's Ceska Sporitelna, KBC's CSOB and Societe Generale's Komercni Banka, along with the sites of some smaller banks, were affected, the banks said.
"Komercni Banka registered a DDoS (distributed denial of service) attack on its portals," a spokeswoman said, referring to a common hacker technique under which websites are flooded by a huge number of access requests, overcoming their systems.
"In no way there has been a leak of client data," the spokeswoman added.
Hackers had on Monday and Tuesday attacked some of the main Czech news websites, slowing or crashing their home pages in the latest in a series of cyber assaults on media outlets around the world.
Ceska Sporitelna spokesman Marek Psenicny said the bank's website and internet banking were down but internal system were in order.
"Client data are certainly not threatened. We are investigating the cause and for the time being we have no details," Psenicny said.
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