Federal election monitors visited San Diego County vote centers Tuesday, Nov. 3, as part of what the U.S. Department of Justice called its largest monitoring effort ever.

The DOJ deployed about 1,000 monitors and observers to all 50 states, a first in the agency's history, according to a DOJ announcement. In California, monitors went to San Diego, Los Angeles, Alameda and Sacramento counties, NBC San Diego reported.

San Diego County Registrar Shawn Brom said his office expected at least eight teams of federal monitors at local polling places on Election Day, according to KPBS. Brom said contingencies were in place if any observer tried to overstep.

"We just want to make sure that regardless of the number of election observers that are at any specific location, that they're not interfering with the voters' right to cast a ballot free from any intimidation or harassment," Brom told KPBS.

A spokesperson for the San Diego County Registrar of Voters said the office had been informed that monitors from the DOJ's Civil Rights Division were visiting vote centers to check compliance with federal laws on language assistance and voter accessibility, according to ABC 10News.

The monitors' purpose, according to the DOJ, is checking compliance with federal voting rights statutes including the Voting Rights Act (VRA), the National Voter Registration Act and the Americans with Disabilities Act (ADA). The effort is coordinated by the DOJ's Civil Rights Division.

Assistant Attorney General Harmeet K. Dhillon of the Civil Rights Division said in a statement that the deployment pursued "transparency for elections in an assertive and nondiscriminatory manner."

Under California state code, observers are not allowed to talk to voters or otherwise interfere in the voting process, KPBS reported. Brom said San Diego County had received federal subpoenas and complied with the law as needed.

The deployment came amid a legal fight between the Trump administration and California over ballots cast by about 20,000 people the DOJ identified as potential noncitizens. A federal judge in Los Angeles, a federal appeals court and the U.S. Supreme Court all rejected administration requests for a restraining order that would have barred the state from tallying those ballots, NBC San Diego reported. State and local officials said that while individual instances of illegal voting may occur, there is no evidence of widespread fraud influencing election outcomes, according to NBC San Diego.

The Los Angeles Times reported that the DOJ removed several sworn law enforcement officers from its pool of volunteer monitors after a review with federal agencies, according to a court filing Tuesday. The remaining monitors were directed to dress in business casual and were forbidden from wearing insignia, carrying firearms or attempting to arrest would-be voters, the Times reported.

State Attorney General Rob Bonta said California deployed its own election observers in partnership with the Secretary of State's Office. On the social media platform X on Nov. 3, Bonta wrote that his office had sent observers "to ensure that voters felt safe, that the law was followed, and that no one was discouraged from casting a ballot," NBC San Diego reported.

Gov. Gavin Newsom posted a video on X on Nov. 2 warning against interference. NBC San Diego reported Newsom wrote: "If you interfere with voters or tamper with ballots, you will be prosecuted with a felony."

Voters with questions or complaints about federal voting rights can call the DOJ's election hotline at 1-800-253-3931. Polls close at 8 p.m. statewide.