LOS ANGELES (CBSLA) – Large stashes of weapons — including assault rifles, ghost guns and ammo – were seized as part of a series of raids over the past month across California targeting convicted criminals who are prohibited from owning weapons.

Weapons and ammo seized in a raid May 11, 2020, at a residence in Lancaster, Calif. (Credit: California DOJ)

One dozen raids were conducted across the state by special agents with the California Department of Justice, including three in the Southland, California Attorney General Xavier Becerra reported Tuesday.

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The raids were the result of background checks done on individuals who had attempted to purchase ammunition. In California, background checks are required for anyone looking to buy ammo, under a law which was overwhelmingly passed by voters back in 2016 under Proposition 63.

51 weapons were confiscated in total, including four assault rifles and two ghost guns. More than 28,000 round of ammunition and 123 magazines were also seized, including 33 large-capacity magazines. 120 grams of meth and heroine was also discovered.

So-called ghost guns are made by individuals and have no serial numbers, which make them nearly impossible to track because they are not registered.

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A residence in Woodland Hills was raided May 4, a second residence in Moreno Valley was raided May 7 and a third in Lancaster on May 11.

In the Lancaster raid, authorities confiscated three handguns, four rifle lower receivers, 12 large-capacity magazines, 13 standard magazines and approximately 2,115 rounds of ammo, the Justice Department said. Rene Navas was arrested.

The people who were targeted in the raids are in the state’s Armed and Prohibited Persons System (APPS) database, which identifies those prohibited from owning guns because of their criminal record.

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About 400 APPS cases since the coronavirus pandemic began, the justice department said.