Question: What was the official communication including over 100 emails which contained classified information which was investigated by the 7th director of the Federal Bureau of Investigation?
Sentence (from "Hillary Clinton email controversy"): In March 2015, it became publicly known that Hillary Clinton, during her tenure as United States Secretary of State, had used her family's private email server for official communications, rather than official State Department email accounts maintained on federal secure servers.
Relevant evidence: No