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CBS News has learned that William Russell, a close adviser to former President Donald Trump, received a subpoena Wednesday related to a Department of Justice investigation into the Jan. 6 Capitol riot and efforts to overturn the election.

Russell, 31, was often seen by Trump’s side, serving as White House deputy director of Advance and Trip Director. He was with the former president for part of the day on Jan. 6, 2021, and moved to Florida to continue working for Trump after his presidency.

FBI personnel visited Russell’s Florida home for questioning Wednesday morning but he was out, according to a person familiar with the matter. Investigators later reached him by phone and served a subpoena via email. 

A lawyer for Russell, Derek Ross, did not reply to a request for comment.

In July, Marc Short, a top aide to former Vice President Mike Pence, testified under subpoena before a grand jury as part of the government’s investigation. Former White House attorneys Pat Cipollone and Pat Philbin also appeared before a grand jury in this matter.

Russell, a Mississippi native, started working at the White House in 2017.

Federal investigators are also engaged in a separate inquiry into Trump’s handling of classified and presidential records. A judge in that case this week ordered a special master, or independent third party, be assigned to sift through the thousands of items the FBI seized in its Aug. 8 search at Trump’s Mar-a-Lago estate.