Greek police said Monday they had arrested an 18-year-old suspected of hacking into the justice ministry's website earlier this month, an attack claimed on behalf of online hackers group Anonymous.
The "Anonymous" hacking group on Tuesday claimed to have shut down the website of security firm Combined Systems, which it accused of providing the tear gas used in crackdowns on protests.
The website of the Central Intelligence Agency was briefly inaccessible on Friday after the hacker group Anonymous claimed to have knocked it offline.
The European parliament website came under cyber attack Thursday but hackers failed to penetrate the assembly's internal network, a spokesman said.
Arab hackers claimed responsibility Wednesday for a series of attacks on prominent Israeli websites, including that of daily newspaper Haaretz.
The computer hacker group Anonymous attacked websites of Brazil's federal district Saturday as well as one belonging to a Brazilian singer to protest the forced closure of Megaupload.com.
US online shoe seller Zappos.com was notifying some 24 million customers Monday that a hacker had gained entry to its computer network, but said credit card data was not affected.
The websites of Israeli national carrier El Al and the Tel Aviv Stock Exchange (TASE) were both offline on Monday morning, hours after they were reportedly threatened by a Saudi hacker.
Howard Stringer, the Welsh-born American head of Japanese games, music and electronics giant Sony, is to step down as the firm's president, reports said Saturday, while remaining CEO and chairman.
Japanese game developer Square Enix said that servers containing data on 1.8 million customers had been hacked, but said the extent of the damage was not yet known.