By Raphael Satter and AJ Vicens

WASHINGTON (Reuters) -Christopher Krebs, whom President Donald Trump fired as head of the Cybersecurity and Infrastructure Security Agency in 2020, said on Wednesday he is leaving cybersecurity company SentinelOne (NYSE: S ) following pressure from Trump.

An email from Krebs, posted to SentinelOne’s website, said he offered his resignation last week after Trump singled Krebs and SentinelOne out for punishment, part of a campaign of retribution aimed at former officials that Trump has deemed insufficiently loyal.

"This is my fight, not the company’s," the email said.

Trump fired Krebs from CISA in November 2020 following his refusal to endorse the president’s false claim that the election had been rigged by his then-opponent, former President Joe Biden.

Last week, Trump signed an order that stripped Krebs and employees of the firm of their security clearances. The rationale for targeting SentinelOne, whose products are used to fight hackers and cybercriminals, was never publicly explained.

The targeting of Krebs and his company fits within Trump’s wider campaign to use the might of the U.S. government to crush his political opponents. And while many in the cybersecurity community privately expressed sympathy with Krebs, few industry leaders have spoken out publicly.

Last week, Reuters asked 33 cybersecurity firms for their reaction to the pressure being brought to bear on Krebs and SentinelOne. All either declined comment or didn’t respond.

CISA declined to comment on Krebs’ resignation. The White House did not immediately return a message seeking comment.