RFE/RL stated the attacks started on the website for Belarus service and spread to other RFE/RL sites and other organizations in Minsk.
RFE/RL believe the attacks are attempts by regional governments to censor news:
"RFE/RL President Jeffrey Gedmin said he is deeply concerned by the attacks. "If free and independent media existed in these countries where we're working and broadcasting, we would have no reason to exist," Gedmin said. "The Belarusians, the Iranians -- they all have basically the same objective. They see free information -- flowing information of ideas and so forth -- as the oxygen of civil society. They'll do anything they can to cut it off. If it means jamming, if it means cyberattacks, that's what they'll do."
US radio websites in Eastern Europe hit by cyberattack: bosses
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Belarus: RFE/RL Cites Online 'Solidarity' in Face of Cyberattack
U.S. Denounces Attack On RFE/RL Websites