After several Czech news sites were taken down by DDoS attacks from within the country earlier this week, the Czech central bank, the Prague Stock Exchange, and several of the country's leading commercial banks were recently hit by DDoS attacks from abroad that either slowed or blocked access to their online services.

"The largest Czech bank, CSOB, said the cyber attack which disabled its online services in the morning had come from abroad," Reuters reports. "The Web site became operational again after CSOB blocked access to it from countries from which the attack came, it said, without disclosing which countries those were. The online banking sites of Erste Group Bank's Ceska Sporitelna, Societe Generale's Komercni Banka and some smaller banks also suffered attacks that shut down their Internet banking and other online services."

"'The cause of the collapse was an external attack that targeted not only Ceska Sporitelna. The bank's internal systems were not disrupted, clients' data and their deposits were not jeopardised, automatic teller machines operated normally," Marek Psenicny, from Ceska Sporitelna's press department, said," The Czech News Agency reports.

"The Czech Police said Wednesday they are analyzing all the cases but are currently unable to confirm the location of the hackers or provide further details," writes The Wall Street Journal's Sean Carney.