A Fox News contributor was punched in the face during a pro-union protest Tuesday in Michigan, one of a series of confrontations between union demonstrators and opponents on the day the state Legislature approved so-called "right to work" legislation that unions oppose.

Steven Crowder, a conservative comedian and Fox News contributor, had spent the day questioning demonstrators, and video he posted on YouTube showed some of them becoming verbally aggressive, with one telling him, "get the f--- out of my face!"

Another protester can be seen later in the video punching Crowder in the face before being restrained by another man.

Crowder later posted photos on his Twitter account showing a chipped tooth and "minor cut on forehead." He told the website TheBlaze.com that the scuffle started when protesters tried to tear down a tent set up by conservative organization Americans for Prosperity.

"They were trying to tear down the tent and people were trying to pull them off. ... And as they did that, a few people tripped,” he told the website. “This guy tripped over a tent peg and then got up and hit me.”

The Lansing Police Department did not immediately respond to a request for comment, but a spokesperson said police would have further information on the incident some time Tuesday night.

Gov. Rick Snyder signed the legislation Tuesday evening after the state House gave final approval of the bills, which bar unions from collecting mandatory fees from workers they represent under collective bargaining agreements.

Earlier Tuesday, two people were arrested after trying to get into a Michigan state building where Snyder has an office.

By evening, dozens of state troopers in riot gear swept protesters away from the building. State police accompanied by sheriff's deputies on horses moved shoulder-to-shoulder to clear the area across the street from the Capitol. Some people who refused to move were physically picked up.

The new laws deliver a blow to the labor movement in the heart of the U.S. auto industry. One bill dealt with public sector workers, the other with government employees. Both measures cleared the Senate last week.

"There will be blood, there will be repercussions," state Democratic Rep. Douglas Geiss, speaking on the House floor on Tuesday, warned ahead of the votes.

Earlier in the day, two state school districts closed after hundreds of teachers called out, presumably to join the protests.

FoxNews.com confirmed that the Warren school district had to close Tuesday after so many teachers called out absent; WDIV in Detroit reported that the Taylor school district had to do the same. A statement from the Warren system said that by 8 a.m. local time, 750 staff members had called out.

Fox News' Mike Tobin and The Associated Press contributed to this report.