Adm. Mike Rogers, director of the National Security Agency, plans to retire in the spring, according to reports.

Rogers, who oversees U.S. Cyber Command, has already notified agency staff of his decision to step down, according to Reuters. President Trump is expected to nominate a new NSA director this month, with Senate confirmation coming in the next few weeks, Politico reported.

The Navy admiral was tapped to lead the agency in 2014 in the wake of whistleblower Edward Snowden’s revelations about the agency’s surveillance of Americans.

In recent years, the NSA has struggled to retain its top personnel and has been hit with significant leaks. Several hundred hackers, engineers, and data scientists have left the spy agency since 2015, sources told the Washington Post.

The top candidates for Rogers’ position reportedly include Army Lt. Gen. William Mayville, Marine Corps Lt. Gen. Vincent R. Stewart, Army Cyber Command head Lt. Gen. Paul Nakasone, and Navy Vice Adm. Michael Gilday.