California voters have passed Proposition 63, making it the first state in the country to require background checks for the sale of ammunition, just like the ones already required for the sale of guns.

Additionally, the referendum passed Tuesday requires gun owners to immediately report lost or stolen guns to law enforcement, bans the sale of large-capacity magazines — those with more than 10 rounds of ammunition — and establishes procedures for convicted felons to relinquish their guns. It also makes stealing a firearm a felony.

Lt. Gov. Gavin Newsom, who helped develop the measure, earlier told KQED:

“I think we are having a very important debate in this country about background checks on guns, but a gun has never killed anybody, unless it’s used as a blunt instrument,” Newsom said. “A gun needs a component — and that’s the ammunition — to be deadly. And the reality is today anyone can buy ammunition anywhere. There’s no licensing requirements to buy ammunition. … Any local grocery store, liquor store, can legally sell unlimited rounds of ammunition. You can get truckloads of ammunition sent to your doorstep online. There’s no background checks for the people selling them and there’s no background checks for the people purchasing them."

Though it'll soon become law, some members of law enforcement aren't happy about that. Sheriff Donny Youngblood, president of the California State Sheriffs’ Association, told ATTN: he opposed the measure. “The people who are going to follow the laws are law abiding citizens," he said, "but the criminals are not going to follow any of the new laws and don’t follow any of the old laws.”

Youngblood said he is “disappointed” in what he deems “an attack on the Second Amendment,” but said he would respect and uphold the voters' will. “People have the right to oppose and be for things and that’s the way our country was founded,” he said.

Update: After the measure passed, Lt. Gov. Newsom told ATTN: via email, ""I'm proud to be a Californian, because we defeated the NRA and made historic and unprecedented progress to reduce gun violence."