CHICAGO | Sun Aug 18, 2013 9:58pm EDT

(Reuters) - Illinois Governor Pat Quinn signed a gun-control measure into law on Sunday that expands background checks to cover all firearms purchases in the state, closing what he said was a loophole that exempted gun sales between private parties.

The new law also requires all gun owners to report any lost or stolen firearms to local police within 72 hours.

"Guns are a plague on too many of our communities," Quinn, a Democrat, said in a statement. "Making sure guns do not fall into the wrong hands is critical to keeping the people of Illinois safe. This commonsense law will help our law enforcement crack down on crime and make our streets safer."

The expanded background checks go into effect on January 1, 2014.

SACRAMENTO -- A package of bills that would once again give California the nation's toughest gun-control laws passed a key legislative hurdle Tuesday, setting up a white-hot Capitol showdown.

The Assembly Committee on Public Safety hearing offered a preview of that battle, as dozens of gun-control advocates -- including some who have lost loved ones to violent crime -- faced off against gun-rights supporters who believe that a basic freedom is threatened.

"This entire package is not focused on trying to prohibit or limit law-abiding citizens from having guns," state Senate President Pro Tem Darrell Steinberg, D-Sacramento, told the committee. "It seeks to close loopholes that were never supposed to exist."

But National Rifle Association lobbyist Ed Worley scoffed at that notion.