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Before President Trump's inauguration, Michael Flynn told Trump's transition team that he was the subject of a federal investigation, two people with knowledge of the case told The New York Times on Wednesday.

Last August, Flynn, Trump's former national security adviser, was secretly hired by a Turkish businessman to launch a campaign discrediting Fethullah Gulen, a Turkish cleric living in Pennsylvania whom Turkish President Recep Tayyip Erdogan blamed for instigating a failed coup last July, but Flynn did not register as a foreign agent, as required by law. On Nov. 30, the Justice Department let him know they were looking into his lobbying work, and he retained a lawyer.

On Jan. 4, Flynn let Don McGahn, the transition team's chief lawyer and current White House counsel, know about the investigation, and two days later, Flynn's attorney alerted transition lawyers. Despite the revelation, Trump still chose Flynn as his national security adviser, giving him access to almost every state secret, the Times said. Flynn was fired after 24 days on the job, when it emerged that he had misled Vice President Mike Pence about the nature of discussions he had with the Russian ambassador to the U.S. The White House would not comment on the report. Before Flynn was fired, acting Attorney General Sally Yates warned the White House that he could be the subject of blackmail due to his conversations with the ambassador.