Chris Krebs, the former senior cybersecurity official whom President Donald Trump fired for affirming the 2020 presidential election was secure, is leaving his private sector cybersecurity job after he and the company were targeted by Trump last week.

Krebs, who led the Cybersecurity and Infrastructure Security Agency during Trump’s first term, is a popular figure at his former agency and in the cybersecurity industry, and the target of ire for proponents of Trump’s false claims that fraud cost him the 2020 election.

On April 9, Trump directed the Justice Department to investigate Krebs and to strip his security clearance and the clearances held by any other SentinelOne employees.

In his resignation email, which SentinelOne has published on its blog, Krebs said: “I don’t shy away from tough fights. But I also know this is one I need to take on fully — outside of SentinelOne. This will require my complete focus and energy. It’s a fight for democracy, for freedom of speech, and for the rule of law.”

“Never forget what’s right, and what you stand for,” he said.

Krebs confirmed his departure to NBC News on Wednesday. The news was first reported by The Wall Street Journal.

The White House did not immediately respond to a request for comment.

In its initial statement to Trump’s actions last week, SentinelOne did not defend Krebs, but said that “we will actively cooperate in any review of security clearances held by any of our personnel — currently less than 10 employees overall and only where required by existing government processes and procedures to secure government systems.