On July 20, 2016, it was reported that the Turkish hacking group Turk Hack Team had claimed credit for a multi-day DNS attack on the servers of the U.S. Library of Congress and hosted systems including Congress.gov, the Copyright Office, Congressional Research Service and others. The attack began on July 17, during the Turkish government’s response to an attempted coup against President Erdogan. Turk Hack Team claimed responsibility on a message board where updates on the availability of websites are posted. The Library of Congress CIO, Bernard Barton, wrote in a blog post that the attack was “a massive and sophisticated DNS assault, employing multiple forms of attack, adapting and changing on the fly,” although it was successfully thwarted.
Source: fcw.com, July 20, 2016