California Governor Jerry Brown signed a sweeping set of gun control measures on Friday, specifically aimed at cracking down on assault weapons like those used in the mass shootings in San Bernardino and Orlando.

Brown signed six bills, one of which will require that gun owners turn in any magazines which can hold more than 10 rounds. Gun owners will also have to undergo a background check before purchasing ammunition. The Democratic governor also banned "bullet buttons," which enable quick magazine changes on a military-style assault weapon.

"My goal in signing these bills is to enhance public safety by tightening our existing laws in a responsible and focused manner, while protecting the rights of law-abiding gun owners," Brown wrote on Friday.

He vetoed several gun control bills, including one which would have given permission to co-workers, teachers, and mental health professionals to request orders banning apparently dangerous people from buying guns.

California already has some of the most stringent gun laws in the US. But after a husband and wife went on a gun rampage in the southern California city of San Bernardino in December, killing 14 and injuring another 21, lawmakers vowed to pass legislation which would close loopholes in the state's gun laws.

Reuters reports that Democrats in the legislature rushed the measures through before summer break, as part of an effort to thwart a competing gun control bill headed for the November ballot.

Brown's decision to sign those measures has sparked rage among gun-rights advocates.