Former Speaker Newt Gingrich (R-Ga.) on Sunday criticized the violent protests that have been taking place at presumptive GOP presidential nominee Donald TrumpDonald John TrumpTrump conversation with foreign leader part of complaint that led to standoff between intel chief, Congress: report Pelosi: Lewandowski should have been held in contempt 'right then and there' Trump to withdraw FEMA chief nominee: report MORE's rallies.

"The country will become enraged," if the violent anti-Trump protests continue into the convention and into the fall," Gingrich said on "Fox News Sunday."

ADVERTISEMENT

"Donald Trump is serious about change in Washington."

Protests against Trump erupted last week while the held a rally in San Jose, Calif. An American flag was set on fire, while other people waved Mexican flags. Fights also broke out between Trump supporters and protesters, and some protesters were seen lighting one of Trump's "Make America Great Again" hats on fire.

Democratic presidential front-runner Hillary ClintonHillary Diane Rodham ClintonQueer Marine veteran launches House bid after incumbent California Rep. Susan Davis announces retirement Poll: Trump neck and neck with top 2020 Democrats in Florida Former immigration judge fined, temporarily banned from federal service for promoting Clinton policies MORE's campaign condemned the violence, saying "violence against supporters of any candidate has no place in this election."

In the interview Sunday, Gingrich continued to defend the presumptive GOP nominee when asked if Trump was too divisive.

"When people see the American flag being burned, they don't side with the people burning the American flag," he said. 

"This is 1968 all over again. This is the hard left saying if you don't do what we want, we're going to be physically violent."

Gingrich said he doesn't think that's sustainable and slammed what he called the "hard left."

"I think the American people will be repulsed by the idea that the hard left gets to dictate to the rest of us."