As the Trump administration seeks to tighten federal control over elections ahead of the midterms, the head of the Justice Department’s civil rights division has sent letters to state election officials warning them of “potential criminal penalties for those who fail to carry out their duties” in relation to federal election laws — including preventing noncitizens from voting. 

“In addition to the Civil Rights Division’s authority to seek injunctive relief for violations of these laws, we are also authorized to prosecute criminal violations,” wrote Harmeet Dhillon, Assistant Attorney General for Civil Rights at the DOJ, according to a copy of letters obtained by ABC News. 

One election official who received a letter — which went to at least six states, including Nevada, Arizona, and Colorado — told ABC News they found it “threatening.”

Noncitizens voting in U.S. elections is illegal and experts say it is exceedingly rare, but President Donald Trump has publicly focused on it — claiming without evidence it is widespread. According to a 2017 study of 42 jurisdictions by the nonpartisan Brennan Center, noncitizen voting accounted for 0.0001% of votes in the 2016 election in those areas.

The DOJ’s Civil Rights Division, which has previously sent other letters to states regarding elections, has made the issue of noncitizen voting a priority. The current letter said it was serving as a “notice” of the federal laws that apply to state and local elections. 

“Federal law mandates that state and local election officials properly maintain election records and undertake certain actions to ensure that only eligible U.S. citizens cast votes in elections for federal office,” the letters said. 

The letters request that the states respond within five days “informing us how the state … intends to ensure it is complying with these federal laws.”

In a statement, Nevada Secretary of State Francisco Aguilar said, “There are already numerous safeguards in place to prevent noncitizens, or anyone ineligible to vote, from casting a ballot.“

“This new request may seem straightforward, but it’s just another attempt from the Trump Administration to create doubt surrounding our elections just ahead of the midterms,” he said.

A Justice Department spokesperson did not immediately respond to a request for comment from ABC News.