More than 450 people in Florida have been ordered to turn over their guns under a law passed after February's deadly school shooting at Marjory Stoneman Douglas High School.

ABC Action News in Tampa reported a majority of the cases that fall under the Risk Protection Act involve people with a history of mental illness who threaten to hurt themselves. The measure, referred to as a "red flag" law, allows family members or law enforcement to seek a court order to temporarily restrict someone's access to firearms if it's believed they are a danger to themselves or others.

Florida officials said they have taken in about 200 firearms and around 30,000 rounds of ammunition.

The law also raised the minimum age to buy a rifle to 21 and established a three-day waiting period on firearm purchases.

Thirteen states currently have red flag laws in place. A red flag bill was introduced in Alabama during the last legislative session but failed to make to a vote.

The laws have the backing of the NRA, which has pushed back on almost every other measure to curb gun ownership.

"We need to stop dangerous people before they act. So, Congress should provide funding for states to adapt risk protection orders," Chris Cox, executive director for the NRA's Institute for Legislative Action, said.

Florida Gov. Rick Scott signed the measure shortly after 17 people were killed at the shooting at Marjory Stoneman Douglas High School in Parkland, Fla. The suspect in the case, Nikolas Cruz, had a history of troubling behavior and disciplinary issues at the school.