The Michigan Capitol in Lansing is on lockdown on Thursday afternoon after more than 1,000 activists flooded the building to protest new legislation that would weaken the power of labor unions in the state.

Michigan police arrested several protesters who tried to rush the Senate floor. Police also sprayed mace into the protesting crowd at one point, according to the Detroit Free Press. Police told CNN that they were forced to lock the doors when the building reached capacity (people are able to exit). Anyone who doesn't leave the building by 5:30 ET will face arrest. The bill passed the House this afternoon.

Republican Gov. Rick Snyder has said the legislation is not antiunion. The proposed bill, called "right to work" legislation, bans the practice of requiring all employees who benefit from a labor contract to pay union dues. Indiana passed a similar bill earlier this year.

Michigan House approves right-to-work legislation

Brett Brown or Owosso, Mich., chants as Pro-union demonstrators crowd the Rotunda in Lansing, Mich., to chant Wednesday afternoon Dec. 5, 2012, in the Capitol after House and Senate Democrats said there was a possibility of "Right To Work" legislation coming up for a vote. Eight people were arrested in similar protests in the Capitol on Thursday. / AP Photo/Detroit News/Dale Young

Updated 5:43 PM ET

LANSING, Mich. The Michigan House has voted to approve right-to-work legislation for private-sector workers.

House members voted 58-52 to approve the measure Thursday afternoon as hundreds of union activists protested loudly in the state Capitol halls in Lansing. Only Republicans voted in favor.

The Senate is debating similar legislation. Minority Democrats are offering a series of amendments, all of which majority Republicans have voted down.

Gov. Rick Snyder and legislative leaders announced earlier Thursday they would try to rush the legislation to enactment in the session's final days.

Meanwhile, hundreds of chanting and cheering protesters have streamed back into the Michigan Capitol after receiving a court order saying that the building must reopen.

The pro-union crowd walked in as lawmakers were debating right-to-work legislation limiting union powers. The Republican-led House subsequently passed the bill with no Democratic support.

They rejoined other protesters who were in the building when police temporarily closed it hours earlier because of safety concerns.

State police Inspector Gene Adamczyk says a judge ordered the Capitol reopened and authorities did so despite safety concerns.

Many of the protesters chanted "Whose house? Our house!" and stomped as they ringed the Rotunda.

Adamczyk said eight people were arrested for resisting and obstructing when they tried to push past two troopers guarding the Senate door. He said the troopers used chemical spray after the people refused to obey orders to stop.

CBS Detroit affiliate WWJ reports that about 200 demonstrators were inside the building when police put it in "lockdown mode," meaning people already indoors were allowed to stay, but no one was allowed to enter.

"The State Police are very concerned about structural damage to the building," reports Tim Skubick, WWJ Lansing Bureau Chief. "A state trooper just told us they don't want this to turn into Wisconsin."

Wisconsin became the focus of national attention and protests when Republican Gov. Scott Walker pushed through legislation to end collective bargaining for most public workers.