Legislation approved Thursday by the state Senate would send more money to a program unique to California that seizes guns from people who are prohibited from having them.

The bill authorizes $24 million for the state Department of Justice's Armed and Prohibited Persons program, which is the only one of its kind in the nation. It prohibits gun ownership for people convicted of a felony or a violent misdemeanor, who are subject to a domestic violence restraining order or who are determined to be mentally unstable.

The department has confiscated more than 10,000 weapons under the program since 2006 but has a backlog of nearly 20,000 people because it has too few agents to go after the weapons. Those individuals own about 39,000 handguns and 1,600 assault weapons, said Sen. Mark Leno, D-San Francisco, the author of SB140.

The additional money would come from a surplus in fees paid for firearms purchases. It would let the department hire six supervisors, 30 special agents and support staff to create six new teams to seize the weapons.

They use a computerized system that cross-matches five databases to identify people who bought guns but are not allowed to own them.

It's the first bill to be considered by the Legislature from among the dozens of gun control measures introduced after recent mass shootings, particularly the Newtown, Conn., school massacre.

"Knowing that there are 40,000 weapons out there today, if there were to be — heaven forbid — anything approaching the Newtown tragedy here in California by one of these 19,000-plus individuals, and we were sitting on $25 million, doing nothing with it because we were squabbling over this little point or this little point, I don't know how any of us would sleep at night," Leno said. "We have a chance to get those weapons now. The money's there."

Senators passed the emergency legislation 31-0, with support from eight Republicans. If it is approved by the Assembly and signed by Democratic Gov. Jerry Brown, the measure would take effect immediately.