US federal investigators have identified more than 400 suspected noncitizens registered to vote in Washington state, with approximately 1,500 instances of ballots being cast across multiple elections, Immigration and Customs Enforcement (ICE) said, as authorities investigate allegations of unlawful voting.

In a post on X, ICE said Homeland Security Investigations (HSI) and federal partners were investigating the allegations and working to protect the integrity of American elections. The agency said noncitizens are not permitted to vote in federal elections and warned that those violating federal election laws would be held accountable. The announcement follows a disclosure by the US Department of Justice (DOJ) that investigators had identified more than 400 noncitizens registered to vote in Washington, some of whom allegedly cast ballots in multiple elections over several decades.US Justice Department challenges California over 20,000 ballots linked to suspected noncitizensFederal investigators reviewed immigration recordsNeil Floyd, acting US attorney for the Western District of Washington, said investigators identified the individuals by reviewing records maintained by US Citizenship and Immigration Services (USCIS).

According to a Fox News report, the records showed that some people who applied for certain immigration benefits had also voted in elections.

Floyd said investigators had counted approximately 1,500 instances of noncitizens casting ballots. While some individuals allegedly voted only once or a few times, others were linked to as many as 27 instances of voting.

Floyd said the earliest cases could date back to the late 1980s or early 1990s.

He also said he had not established whether any of the individuals had voted in the upcoming midterm elections.US calls report on Trump’s deportation drive fake news; claims historic drop in illegal immigrationGreen card holders among those identifiedFederal officials said many of the individuals identified were green card holders, or lawful permanent residents. Authorities raised concerns about Washington's Motor Voter program, which connects voter registration with the state's Department of Licensing.

According to the federal notice cited by Fox News, some green card holders said they had been registered without their knowledge. They allegedly assumed they were eligible to vote after receiving ballots by mail.

However, the Washington secretary of state's website says eligible residents are automatically registered only after providing proof of US citizenship during the driver's license or identification card registration process.

The DOJ has asked Washington state to set aside ballots cast by the identified individuals until their citizenship status can be confirmed, the report said. Federal probe raises immigration concernsFederal officials warned that unlawful voter registration or voting could carry criminal consequences and affect applications for US citizenship, depending on individual circumstances.

The Washington investigation comes amid a broader federal crackdown on alleged noncitizen voting. The Department of Homeland Security told Fox News that dozens of noncitizens had been arrested nationwide over alleged voter registration or voting violations. At least 18 were reported to have voted in a federal election. The allegations against the individuals identified in Washington remain subject to investigation and verification.