In March 2016, the personal Gmail account of John Podesta, a former White House chief of staff and chair of Hillary Clinton's 2016 U.S. presidential campaign, was compromised in a data breach accomplished via a spear-phishing attack, and some of his emails, many of which were work-related, were hacked. Cybersecurity researchers as well as the United States government attributed responsibility for the breach to the Russian cyber spying group Fancy Bear, allegedly two units of a Russian military intelligence agency.