According to Uproxx, the Florida senator made a decision to fire his Chief of Staff Clint Reed for "improper conduct" with subordinates the same day he was informed of the allegations.
The Florida Republican's announcement made no mention of the chief of staff's name.
Reed, who describes himself on social media as Rubio's chief of staff, did not return messages seeking comment. In the picture, Rubio takes questions from reporters about the relief effort in Puerto Rico following Hurricane Maria in Washington, DC., Sept. 26, 2017.
Rubio with Clint Reed (right), fired last night. He joined Mr. Rubio's staff in December 2016 after managing his presidential campaign in Iowa, South Carolina and Florida.
Reed had been Rubio's chief of staff for the last year and previously served as Rubio's campaign manager for his Senate re-election in 2016.
US Senator Marco Rubio has announced the firing of his Chief of Staff for alleged misconduct. Sen. Immediately upon receiving this complaint, I along with our General Counsel, began an investigation of this matter. It said Mr. Rubio, a Republican, was directly informed of the allegations on Friday afternoon.
Mr. Rubio's statement said his office would "not be disclosing any further details about the incidents which occurred". Rubio also said his office is trying to make sure "those impacted by this conduct have access to any services they may require now or in the future", suggesting there was more than one staffer who was affected.
That is why, in the evening, Rubio "traveled from Florida to Washington D.C." in order to terminate Reed's employment "effective immediately". Rubio's office plans to notify appropriate congressional and Senate administrative offices of the situation.