A gun violence prevention group sued Kansas Governor Sam Brownback and the state's attorney general on Wednesday, challenging a one-year-old state law on the grounds that it violates the U.S. Constitution by nullifying federal laws aimed at reducing firearms violence.

"Neither the Kansas legislature, nor any state legislature, is empowered to declare federal law 'invalid,' or to criminalize the enforcement of federal law," the lawsuit said.

The Brady Campaign to Prevent Gun Violence filed the lawsuit in U.S. District Court in Kansas City, Kansas, naming the governor and Attorney General Derek Schmidt as defendants. The group is seeking a permanent injunction prohibiting enforcement of the Kansas law.

Brownback, who signed the law in April 2013, vowed to defend the measure, called the "Second Amendment Protection Act."

"The right to keep and bear arms is a right that Kansans hold dear," Brownback, a Republican, said in a statement. "It is a right enshrined not only in the Second Amendment to the United States Constitution, but also protected by the Kansas Bill of Rights."

The law says that firearms made in Kansas are not subject to any federal law or regulation, including a gun or ammunition registration program. It also provides a nullification clause, deeming "void and unenforceable" any laws or regulations that the state deems to be a violation of the Second Amendment.

According to the complaint, the Kansas law violates provisions that give final power to interpret the U.S. Constitution to federal courts, not state legislatures. The Brady group also said the law is contrary to a 1958 U.S. Supreme Court ruling that found any state law claiming to nullify federal law as unconstitutional.

Jonathan Lowy, director of the legal action project at the Brady Center, said that the law in Kansas is contrary to public safety and common sense, and that it is part of a larger campaign by the gun lobby to eliminate restrictions on guns.

"It should be called the 'Gun Violence Preservation Act,'" said Lowy.

The law allows for the unregulated manufacture and sale of Kansas firearms, firearm accessories and ammunition, and allows for the purchase of weapons with no background checks or records kept, and would allow for the sale of Kansas handguns to people as young as 18, the lawsuit said. It also would make it a crime for local police to refer gun crimes to federal agencies for prosecution, the lawsuit states.

Last year, a federal appeals court struck down a 2009 Montana law that sought to prohibit federal regulation of guns made in that state.

Lawmakers in Missouri have been trying to pass a similar measure. Last year, Missouri Governor Jay Nixon, a Democrat, vetoed one such measure.