Ben Brewer/Reuters
A security guard ejected Ramos from a press conference in Iowa after he refused to sit down and wait to be called.
"Go back to Univision," Trump said, as Ramos was escorted out.
As Ramos waited outside, a man wearing a Trump sticker on his shirt approached the Univision host and confronted him about his behavior during the press conference.
"You were very rude, it's not about you," the man said to Ramos. "Get out of my country."
"I'm a US citizen, too," Ramos replied.
"Yeah, well, whatever," the man said. "Univision, no."
Ramos and the man traded barbs before a police officer interjected to separate the men.
Watch the video below, via Univision:
The Univision anchor was later allowed back into the press conference. He pressed Trump on the specifics of the real-estate magnate's controversial immigration plan, noting that it would likely be unconstitutional and logistically impossible.
"How are you going to deport 11 million people? Are you going to bring in the army?" Ramos asked.
"We'll going to do it in a very humane fashion. Believe me. I have a bigger heart than you do," Trump said.
When Ramos asked Trump about his unpopularity with Latino voters, Trump shot back, raising his pending lawsuit against Univision.
"How much am I suing Univision for right now? Do you know the number? I know you're part of the lawsuit," Trump said.
AP
Trump has prominently feuded with Ramos' network, filing a lawsuit against Univision after it severed ties with him over comments that Trump made accusing the Mexican government of sending "rapists" and drug dealers across the border.
Ramos has been highly critical of the reality-television personality's immigration platform, noting that it would require roughly 11 million people living in the US illegally to be deported, which Ramos argues would be both costly and inhumane.
The spat isn't likely to help Trump's perceptions among Latino voters.
A new Gallup poll on Monday showed that Hispanic voters dislike Trump vastly more than any other candidate in the Republican field.