The Trump administration is threatening emergency court action unless California officials investigate potential ineligible voters within 48 hours and set aside ballots from anyone whose citizenship they cannot verify, according to two letters sent to state officials from the Justice Department.

Why it matters: With voting already underway, President Trump 's DOJ could delay ballots from eligible Californians mistakenly flagged as noncitizens and set up a court fight just three weeks before Election Day.

Driving the news: Acting Deputy Attorney General R. Trent McCotter sent a letter Tuesday to Los Angeles County Registrar-Recorder/County Clerk Dean Logan along with a thumb drive of "likely noncitizens who were sent a vote-by-mail ballot," according to a copy of the letter shared with Axios.

McCotter asks local officials to investigate their citizenship status by noon October 15.…