Lawyers for the whistleblower behind the complaint related to President Donald Trump’s call with the leader of Ukraine said this weekend that they have “serious concerns” regarding their client’s safety.

In a letter addressed to acting Director of National Intelligence Joseph Maguire, the lead attorney for the whistleblower, Andrew Bakaj, alluded that the whistleblower is currently under federal protection.

The legal team, he wrote, only expects “this situation to worsen, and to become even more dangerous for our client and any other whistleblowers” who come forward.

“The purpose of this letter is to formally notify you of serious concerns we have regarding our client’s personal safety. We appreciate your office’s support thus far to activate appropriate resources to ensure their safety,” Bakaj wrote in the letter. “The events of the past week have heightened our concerns that our client’s identity will be disclosed publicly and that, as a result, our client will be put in harm’s way.”

“60 Minutes” first reported the contents of the letter, which was forwarded to House Intelligence Committee Chairman Adam Schiff (D-Calif.) and Senate Intelligence Committee Chairman Richard Burr (R-N.C.), as well as the panels’ ranking members.

Attorneys for the whistleblower did not immediately respond to HuffPost’s request for comment. Bakaj shared the document on social media following the release of the “60 Minutes” report.