“The President of the United States just called for the arrest of a sitting Governor,” Newsom wrote on social media. “This is a day I hoped I would never see in America. I don’t care if you’re a Democrat or a Republican, this is a line we cannot cross as a nation — this is an unmistakable step toward authoritarianism.”

The California governor blasted Trump amid the president’s deployment of National Guard troops to the Los Angeles area.

President Donald Trump threatened Monday to arrest Gov. Gavin Newsom, a striking example of Trump attacking a fellow elected official just as National Guard troops deployed in Los Angeles amid protests over immigration actions.