(Reuters) - California Governor Jerry Brown signed several gun control bills into law on Friday, including one measure that raises the minimum age for buying rifles and shotguns from 18 to 21.

The new laws come seven months after a gunman opened fire with a semiautomatic assault-style rifle at Marjory Stoneman Douglas High School in Parkland, Florida, killing 14 students and three adults, the second-deadliest mass shooting at a public school in U.S. history.

The rampage, which authorities say was carried out by a former student who was 19, has spurred unprecedented activism by victims and their families to prevent future gun violence and demanding stricter gun control across the United States.

California already has some of the strictest gun laws in the nation. State Senator Anthony Portantino, the Democrat lawmaker who wrote the bill, said the rampage in Florida along with other shootings at high schools motivated him.

“No parent should have to worry that a gun gets in the wrong hands and commits a heinous and violent tragedy on our school campuses,” he said in a statement.

The new California laws, which go into effect Jan. 1, exempt law enforcement officers and military service members.

Federal law already prohibits people younger than 21 from buying a handgun from a licensed firearms dealer.

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Brown also signed legislation that bans firearm possession for people convicted of serious domestic violence charges along with people who have been hospitalized for mental health problems more than once in one year.

He did not comment on the legislation.

He also signed a bill that makes it easier for family members and police to take firearms and ammunition away from people who are believed to be a threat to commit violence.

Three weeks after the shooting in Parkland, Florida lawmakers raised the legal age for buying rifles and imposed a three-day waiting period on all gun sales.

The National Rifle Association (NRA) responded by filing a federal lawsuit seeking to overturn the new Florida laws, saying they violated Americans’ constitutional rights.

“We will continue to oppose gun control measures that only serve to punish law abiding citizens,” wrote Daniel Reid, the director of the NRA in California, in a letter to state lawmakers, according to the Los Angeles Times.