President-elect Donald Trump slammed what he called "professional protesters" on Thursday, writing on Twitter that the people demonstrating across the country in the wake of his election to the White House were "incited by the media."

"Just had a very open and successful presidential election," Trump wrote Thursday night. "Now professional protesters, incited by the media, are protesting. Very unfair!"

The comment was a brief return to form for Trump, whose Twitter feed has been devoid of any of his characteristically antagonist messages in the two days since he was chosen to become the 45th president of the United States. On Wednesday, he also wrote about his "fantastic" meeting with President Barack Obama.

"Really good meeting, great chemistry," he wrote. "Melania liked Mrs. O a lot!"

Trump's opinion of the protesters appeared to shift overnight.

"Love the fact that the small groups of protesters last night have passion for our great country," he wrote early Friday. "We will all come together and be proud!"

Thousands of people flooded the streets across the country to protest after voters chose Trump to lead the country come January.

Police in Portland, Oregon, arrested 26 people after an anti-Trump protest devolved into a riot on Thursday night.

In Los Angeles, police arrested 185 people and the California Highway Patrol made 30 arrests, KTLA reported. Two people, including a police officer, were injured during the demonstrations.

Anti-Trump protests have taken place in numerous cities, including Chicago, New York, Houston, Minneapolis and Philadelphia.