With examples of Russian-created Facebook pages behind him, Sen. Patrick Leahy, D-Vt., questions witnesses from social media companies during a hearing on Capitol Hill.
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Protesters gather outside as Roy Moore, Republican candidate for U.S. Senate, appears at a mid-Alabama Republican Club's Veterans Day event in Vestavia Hills, Ala., on Saturday.
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This April 3 photo, taken in Washington, DC, shows President Donald Trump's Twitter feed. Some Twitter users argue Trump is violating the First Amendment by blocking people from his feed after they posted negative comments.
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It has become increasingly common for politicians at all levels of government to block followers, whether it's for uncivil behavior or merely for expressing a different point of view.
Twitter ended its advertising relationship with Russia Today and Sputnik on Thursday based on "the U.S. intelligence community's conclusion that both RT and Sputnik attempted to interfere with the election on behalf of the Russian government."
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Twitter officials are expected to meet with Senate Intelligence Committee investigators. Staffers want to know about the use of fake accounts, bots and trolls to influence the trends and topics on the social platform.