If California Gov. Jerry Brown signs a sweeping new gun control bill that would ban the future sales of semi-automatic rifles that accept detachable magazines, the NRA plans to sue, according to Fox News.

Among the bills sent to Brown last month is one that would outlaw an entire class of weapons that includes most assault rifles. It is the latest and most far-reaching attempt to close loopholes that have allowed manufacturers to circumvent previous assault weapon bans enacted in the state since the 1990s. The NRA's Institute for Legislative Action wrote in a post on its website that the bill is unconstitutional and "would make unprecedented changes to California’s already unjust and byzantine 'assault weapon' law." Under current California law, assault weapons can only be used for limited purposes and owners are prohibited from transferring them to anyone in the state. The bill would change the definition of an assault weapon to include any semi-automatic rifle with a detachable magazine or a fixed magazines holding more than 10 rounds of ammunition, according to the group's statement.

“Our right to keep and bear arms has never been as seriously threatened in California as it is today. After years of incrementally adopting gun control measures, this year the Legislature decided to propose new laws adopting everything on the gun ban lobby’s wish list,” the group said.

Sam Paredes, executive director of Gun Owners of California, told the AP last month that “the bill will make half of the rifles in existence ‘assault weapons,’ and make them illegal.”

Brown has until Oct. 13 to decide whether he will sign or veto the bills.