NASHVILLE, Tenn. — Tennessee teachers and staff will be allowed to carry concealed handguns on public school grounds under legislation signed into law by Gov. Bill Lee on Friday.

Lee, a Republican, had announced his support for the proposal just the day before while flanked by top Republican legislative leaders who had helped shepherd the bill through the GOP-dominant General Assembly.

''What's important is that we give districts tools and the option to use a tool that will keep their children safe,'' Lee told reporters.

As the idea of arming teachers began to gain support inside the General Assembly, gun control advocates and families began swarming to the Capitol to show their opposition. During the final vote, protesters chanted ''Blood on your hands'' and many members of the public who oppose the bill harangued Republican lawmakers after the vote, leading House Speaker Cameron Sexton to order the galleries cleared.

According to the statute, which becomes effective immediately, parents and other teachers will be barred from knowing who is armed at their schools.

A principal, school district and law enforcement agency would have to agree to let staff carry guns, and then workers who want to carry a handgun would need to have a handgun carry permit and written authorization from the school's principal and local law enforcement. They would also need to clear a background check and undergo 40 hours of handgun training. They couldn't carry guns at school events at stadiums, gymnasiums or auditoriums.

The legislation is the biggest expansion of gun access in the state since last year's deadly shooting at a private elementary school in Nashville where shooter indiscriminately opened fire and killed three children and three adults before being killed by police.

Lee initially asked lawmakers to keep guns away from people deemed a danger to themselves or others in response to the shooting, the Republican supermajority ignored that request.

Many of the Covenant families had met with Lee and lawmakers hoping to persuade them to drop the idea of arming teachers. In the final days of the legislative session, Covenant families said they had collected nearly 4,300 signatures from Tennesseans against having public school staffers carry weapons on school grounds.

"There are folks across the state who disagree on the way forward, but we all agree that we should keep our kids safe,'' Lee said Thursday.

It's unclear if any school districts would take advantage if the bill becomes law. For example, a Metro Nashville Public Schools spokesperson, Sean Braisted, said the district believes ''it is best and safest for only approved active-duty law enforcement to carry weapons on campus.''