I.R.S. undertakes a security review amid threats to the agency and its employees.

The Internal Revenue Service, which has been attacked by Republican lawmakers and conservative outlets, is looking into its security.

In a letter sent to staff on Tuesday, the I.R.S. commissioner cited an abundance of misinformation and false social media postings, some of them with threats directed at the I.R.S.

The agency has increased engagement with law enforcement and security agencies as a result of the review of existing safety and security measures.

Mr. Rettig assured you that your safety is and will continue to be his top priority.

The security review was reported by The Washington Post.

In the wake of a Democrat-backed bill that gives the tax collector an additional $80 billion to help crack down on tax cheat, there has been a lot of misinformation about the agency. President Biden signed legislation last week that will help the agency hire more than 80,000 employees, upgrade antiquated technology systems and improve its ability to respond to taxpayers.

The additional personnel will not result in increased scrutiny or audits of people who make less than $400,000 a year.

Ms. Yellen told Mr. Rettig that she wanted the agency to focus on tax dodgers and tax evasion.

The investments won't result in households earning $400,000 per year or small businesses seeing an increase in the chances that they are audited relative to historical levels.

The threat that mom-and-pop shops and middle-class Americans will face from a tax collector has spawned a number of false conspiracy theories. Social media is filled with claims that the new agents will be heavily armed, despite the fact that just 1 percent of them will be carrying guns.

Members of congress are still making spurious claims.

The new I.R.S. agents might be coming with loaded AK-15s and ready to shoot some small-business person in Iowa, warned Senator Charles E.

Republicans warn that more I.R.S. agents will lead to more audits of small-business owners and middle-class Americans.

The safety of I.R.S. employees is a top priority according to Ms.