Tennessee Sen. Lamar Alexander, R, fired his chief of staff on Wednesday after the staffer's personal residence was searched in connection to a child pornography investigation.

NBC's Kelly O'Donnell reports on an investigation into Sen. Lamar Alexander's chief of staff for allegations involving child pornography.

Alexander, a veteran senator who's up for re-election in 2014, said that law enforcement agents had conducted a search this morning of the residence of Ryan Loskarn. Alexander announced earlier in the day that Loskarn had been placed on administrative leave, and later released a statement to announce had been let go.

“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 in a statement.

Alexander's legislative director, David Cleary, was promoted to the position.

A chief of staff is typically the most senior staff position in a congressional office. That role carries even more import in an office like Alexander's, which carries a degree of seniority and influence with it.

U.S. Postal Inspectors conducted the raid.

“The Postal Inspectors Service was involved in a law enforcement action in Southeast DC," a spokesman for the agency told NBC News, declining further comment.

NBC News' Kasie Hunt contributed reporting.

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