The Department of Homeland Security says it found thousands of noncitizens on voter registration rolls, according to a draft press release reported by Politico ahead of a planned speech by Trump. The draft document said the registrations were identified in California, Nevada, New Jersey and Pennsylvania.

The reported finding quickly puts voter eligibility and election administration back into the political spotlight. Based on the limited details available, it was not immediately clear how the registrations were identified, whether any of the names were later removed, or whether any ballots were tied to the cases.

Politico reported that spokespeople for the secretaries of state in Nevada, New Jersey and Pennsylvania did not immediately respond to requests for comment. California's top election office was also referenced in the report, though the available snippet did not include a full response.

With the issue emerging just before Trump's remarks, the matter is likely to draw renewed scrutiny from both federal officials and state election administrators. Any confirmed problems involving noncitizens on voter rolls could carry legal and political significance, while the underlying data and verification process are expected to face close review.