Updated 5:18 p.m. | Federal law enforcement agents escorted Sen. Lamar Alexander’s D.C.-based chief of staff from his Southeast Washington home in handcuffs on Wednesday.

Footage from NBC 4

Postal Inspection Service spokesperson Lori McAllister directed all questions related to arrest to the Justice Department.

Capitol Police and the Metropolitan Police Department are not involved in the investigation, spokespeople confirmed.

Senate Sergeant-at-Arms Terrance W. Gainer told CQ Roll Call in an email that he had no further information.

Earlier in the day, Alexander announced that Loskarn had been put on administrative leave as authorities searched his personal residence.

“I was just informed by the United States Senate legal counsel’s office that law enforcement agents are conducting a search of the personal residence of Ryan Loskarn, the chief of staff of my Washington, D.C., office regarding allegations involving child pornography,” the statement from the Tennessee Republican read. “I am stunned, surprised and disappointed by what I have learned. Based on this information, I immediately placed Mr. Loskarn on administrative leave without pay. The office is fully cooperating with the investigation.”

Alexander’s office did not respond to request for comment on the arrest.

Loskarn served as a top staffer to Alexander when the senator was Senate Republican Conference chairman. Because of his position as a key leadership aide, Loskarn appeared on Roll Call’s Fabulous 50 list of influential staffers from 2009 to 2011. Loskarn was taken off the list after Alexander stepped down from leadership. Alexander named Loskarn his personal office chief of staff in 2011.

Loskarn has been a congressional employee since 2000 and has been with Alexander since 2007, according to the database LegiStorm.

Five hours after placing Loskarn on administrative leave, Alexander announced that he was replacing him as chief of staff.

“The courts will judge Mr. Loskarn’s guilt or innocence, but under these circumstances, he cannot continue to fulfill his duties as chief of staff of this office. Therefore, as of today, I have removed him from the payroll,” Alexander said.

Replacing Loskarn is Alexander’s legislative director, David Cleary, who has been working with the Tennessee Republican since 2006. Cleary has been Alexander’s legislative director since 2011 and has been the Republican staff director for the Senate Health, Education, Labor and Pensions Committee since 2012. Alexander is the top Republican on the committee.

“David has worked with me for eight years and fortunately is well-prepared to step into this position,” Alexander said in a statement.

Cleary previously served as a staffer for the House Education and the Workforce Committee when Speaker John A. Boehner of Ohio was that panel’s chairman.

He has also worked as a legislative analyst for the Department of Education. Cleary earned a bachelor’s degree in political science and a master’s degree in public administration from George Washington University.