Calling them “killing machines,” legislation introduced with the backing of the state attorney general would require semi-auto rifles to have their magazines permanently affixed in the state of California.

Two bills debuted by Assembly Democrats with the strong endorsement of Atty. Gen. Kamala D. Harris would effectively close what the lawmakers term the “bullet button loophole” by banning the devices which require a tool to remove an otherwise fixed magazine from a semi-automatic rifle and require guns already fitted with such buttons since 2001 to register them as “assault weapons” under California law.

The framers of the proposals claim that magazines that are non-detachable prevent the rapid reloading that can increase death tolls in mass shootings. The AR-15 style rifles used by terrorists in the San Bernardino shooting last December had their bullet buttons removed after they were illegally acquired through an alleged straw purchase.

“Killing machines have no place on our streets and gun violence must not be tolerated,” said Assemblymember Marc Levine, D-Marin County, co-author of one of the bills and sponsor of the second, in a statement. “This legislation assures that gun manufacturers cannot work around the intent of California’s ban on military-style assault weapons. We raise our children in communities, not war zones.”

Levine’s measure, AB 1664, taken with a companion bill, AB 1663, would classify a semi-automatic centerfire rifle that does not have a fixed magazine with the capacity to accept no more than 10 rounds as an assault weapon under state law and define a “detachable magazine” to mean an ammunition feeding device that can be removed from the firearm without disassembly of the action, including one that can be removed with the use of a tool.

Those with a bullet button would have until 2018 to register their gun and those found after that date with such a device installed on an unregistered rifle would be liable to a felony charge and up to a year in prison.

“Detachable magazines cost lives, and it is more important to save lives during future mass shootings than to be able to reload assault weapons in the blink of an eye,” said Assemblymember David Chiu, D-San Francisco, sponsor of AB 1663.

As an aide to U.S. Sen. Paul Simon, D-Illinois in the 1990s, Chiu worked on gun legislation to include the federal assault weapon ban, before moving into San Francisco city politics with the support of Kamala Harris and Leland Yee. He now holds the third highest-ranking position in the state assembly though only a freshman assemblymember.

Yee, who plead guilty on federal corruption charges last year, backed a similar bullet button ban in 2012 which tanked, while Gov. Jerry Brown vetoed a 2013 bill to do the same thing that made it to his desk.

Now, Harris is supporting Chiu once again in backing the bullet button legislation.

“The devastation wrought by gun violence on innocent victims, children and families in this country is an international embarrassment,” said Harris, who is currently seeking a U.S. Senate seat, in a statement issued by her office. “This is a common sense solution that closes a dangerous loophole in California’s assault weapons ban.”

Gun rights advocates in the state are mobilizing to help stop the latest incremental regulation on firearms in the Golden State and point to Bay area politics as a driving point behind the move.

“Assembly Bill 1663 is yet another misguided attack on the civil rights of law-abiding Californians,” Brandon Combs, president of Firearms Policy Coalition, told Guns.com. “In the wake of a deadly terrorist attack on our soil, fringe San Francisco elitists like Assemblyman Chiu and Attorney General Harris would rather put innocent people in jail than face up to their own failed policies.”

The FPC is actively opposing the measure and is circulating a petition to advocate with lawmakers against the ban.

Gun control groups to include the Law Center to Prevent Gun Violence and the Brady Campaign are supporting the bullet button ban, arguing the devices, only used in California, were a way for gun makers to circumvent state law.

“Since California’s first assault weapons law was passed in 1989 in the wake of the tragic Stockton schoolyard shooting, we have struggled to make it real in the face of the gun industry’s determination to find new ways to evade the law’s intent,” said Amanda Wilcox with the Brady Campaign. “Curbing the ability to rapidly reload will decrease the lethality in future mass shootings and save lives.”