The substance an attacker sprayed on Rep. Ilhan Omar (D-Minn.) during a Minneapolis town hall on Tuesday was found to be apple cider vinegar.

Forensic scientists made the determination “with high probability,” CNN wrote, citing a law enforcement source. The progressive lawmaker’s office later confirmed the finding to the news network.

Omar was addressing the tension that has erupted since federal immigration officers shot and killed two protesters when the suspect, identified as Anthony J. Kazmierczak, sprayed her with liquid from a syringe, The Associated Press reported.

He was pinned to the ground, arrested and booked at the county jail for third-degree assault. Undeterred, Omar spoke for 25 minutes more, PBS reported.

The suspect has expressed support for President Donald Trump online and called Democrats “angry and liars,” according to the public broadcaster.

Ilhan Omar, pictured at a Monday news conference, was sprayed with apple cider vinegar in a recent attack, forensic specialists determined.

Bloomberg via Getty Images

Before the attack, Omar had called for the abolition of Immigration and Customs Enforcement and the resignation or impeachment of Homeland Security Secretary Kristi Noem.

The congresswoman wrote of the incident on social media, “I’m ok. I’m a survivor so this small agitator isn’t going to intimidate me from doing my work. I don’t let bullies win. Grateful to my incredible constituents who rallied behind me. Minnesota strong.”

Omar blamed Trump’s incendiary rhetoric for threats against her and said he had “dementia” and is “obsessed” with her.