Andrew Peek, head of European and Russian affairs at the National Security Council, has been put on administrative leave from his post three months after he started. 

Three sources told Bloomberg on Saturday that Peek was “escorted from the White House grounds on Friday.” Peek and the National Security Council refused to comment, stating they were not authorized to discuss personnel matters.

Earlier on Saturday, Axios reported that Peek was put on administrative leave. The reason for the leave was allegedly a pending security-related investigation unbeknown to the public. 

Before becoming head of European and Russian affairs, Peek served as a deputy assistant secretary of State for Iraq and Iran as a U.S. Army intelligence officer in Afghanistan. He was also a national security adviser for two Republican senators: Sen. Gordon Smith (R-Oregon), and Sen. Mike Johanns (R-Nebraska). 

Peek is the third person to leave this position in the past year. He took office last November after Tim Morrison who previously held the position also resigned. Morrison testified in the House impeachment inquiry that he was told there was quid pro quo in the Ukraine investigation, but that he didn’t think the president’s actions were illegal. 

Morrison had replaced Fiona Hill, who also stepped down from the position and testified in the impeachment inquiry. 

Donald Trump has since been impeached by the House on charges of abuse of power and obstructing Congress. The articles of impeachment were presented to the Senate last week, and the chamber will now complete another investigation to decide whether or not the president should be removed from office. 

Peek was set to attend the Davos summit in Switzerland with Trump from January 21 of January 24 for the World Economic Forum, but was removed last week. The reason for this is still unknown, but it’s assumed it was a result of the security-related investigation.