WASHINGTON - The U.S. Justice Department is warning states that are conducting or considering audits of the 2020 election that they may be using procedures that violate federal protections against voter intimidation and other statutes.

The warning comes as Arizona Republicans continue a controversial review of the 2020 vote count in the state's largest county while Republican officials in four other battleground states where former President Donald Trump lost to President Joe Biden are pursuing similar efforts.

"Election audits are exceedingly rare," the Justice Department said in new guidance on post-election audits issued on Wednesday. "But the Department is concerned that some jurisdictions conducting them may be using, or proposing to use, procedures that risk violating the Civil Rights Act."

Post-election reviews of ballots have long been part of election administration that is handled by election officials. But audits of the 2020 election drawing the Justice Department's attention are unofficial and are being pushed by Republican allies of Trump who allege that the election was marred by widespread fraud, costing Trump his reelection.

In addition to Arizona, Republicans in four other states that Trump lost - Georgia, Michigan, Pennsylvania and Wisconsin - have been pressing ahead with efforts to review the 2020 election results, according to the Brennan Center for Justice.

"I think the reason we're issuing this guidance is to tell jurisdictions generally that we are concerned that if they're going to conduct these audits, so-called audits of the past election, they have to comply with federal law and warning them that they can't conduct these audits in a way that is going to intimidate voters," a Justice Department official said.

FILE - Maricopa county ballots cast in the 2020 election are examined and recounted by contractors working for Florida-based company Cyber Ninjas at Veterans Memorial Coliseum in Phoenix, Arizona, May 6, 2021.

In its guidance document, the department outlined two broad concerns about post-election audits. The first concerns the preservation of election records. Under federal law, election officials are required to keep voting records for 22 months after an election.

"This means that jurisdictions have to be careful not to let those ballots be defaced or mutilated or lost or destroyed as part of an audit," the Justice Department official said during a press call with reporters. The official spoke on condition of anonymity.

The Justice Department's second concern relates to voter intimidation. Under the 1965 Voting Rights Act, it is illegal to intimidate voters or those intending to vote. Examples of voter intimidation cited in the document include taking down the license plate numbers of individuals attending voter registration meetings.

"If a jurisdiction is going to conduct one of these audits it has to do so in a way that's not going to intimidate voters and deter them from voting in future elections," the official said.

The guidance echoes a warning the Justice Department gave to Arizona Republicans about their post-election audit.

In a letter to a top Republican official, Principal Deputy Assistant Attorney General Pamela Karlan raised questions about plans by GOP-hired auditors to go door to door "to confirm if valid voters actually lived at the stated address." The planned canvassing "raises concerns regarding potential intimidation of voters" in violation of federal law, the letter stated.

In response, the Republicans dropped their planned canvassing. While the Justice Department hasn't issued similar letters to other states, "we're keeping a close eye on what's going on around the country," the official said.

In Pennsylvania, a state Trump lost by more than 80,000 votes, state lawmaker Doug Mastriano this month launched what he called a "forensic investigation" of the 2020 election, requesting information from three counties. Democrats have questioned the legality of the audit.

In Wisconsin, another state Trump lost, Rep. Janel Brandtjen, chair of the Wisconsin State Assembly elections committee, announced on Monday that her committee will request additional information to ensure a "comprehensive, forensic examination" of 2020 votes.