Washington (CNN) Sen. Marco Rubio has fired his chief of staff over "allegations of improper conduct" with a subordinate, his office announced late Saturday night.

"Yesterday afternoon, I was made aware, for the first time, of allegations of improper conduct by my chief of staff while under the employment of my office," Rubio said in a statement.

The statement did not mention Rubio's chief of staff by name, but he has been identified as Clint Reed on his social media accounts, and a former aide confirmed he was the chief of staff. CNN has attempted to contact Reed for comment.

Clint Reed, former chief of staff to Sen. Marco Rubio.

"By early this afternoon, I had sufficient evidence to conclude that while employed by this office, my chief of staff had violated office policies regarding proper relations between a supervisor and their subordinates. I further concluded that this led to actions which in my judgement amounted to threats to withhold employment benefits."

The Republican lawmaker said he flew from Florida to Washington D.C. on Saturday and "terminated his employment effective immediately."

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