MINNEAPOLIS (AP) — The Justice Department has charged a man who squirted apple cider vinegar on Democratic U.S. Rep. Ilhan Omar at an event in Minneapolis, according to court papers made public Thursday.

The man arrested for Tuesday’s attack, Anthony Kazmierczak, faces a charge of forcibly assaulting, opposing, impeding and intimidating Omar, according to a complaint filed in federal court.

Authorities determined that the substance was water and apple cider vinegar, according to an affidavit. After Kazmierczak sprayed Omar with the liquid, he appeared to say, “She’s not resigning. You’re splitting Minnesotans apart,” the affidavit says. Authorities also say that Kazmierczak told a close associate several years ago that “somebody should kill” Omar, court documents say.

It was unclear if Kazmierczak had an attorney who could comment on the allegations. A message was left with the federal defender’s office in Minnesota.

Kazmierczak has a criminal history and has made online posts supportive of President Donald Trump, a Republican.

Omar blamed Trump on Wednesday for threats to her safety. The attack came during a perilous political moment in Minneapolis, where two people have been fatally shot by federal agents during the White House’s aggressive immigration crackdown.

Trump has accused Omar of staging the attack, telling ABC News, “She probably had herself sprayed, knowing her.”