More than 100 guns and 49,000 rounds of ammunition were seized during a five-day operation across Los Angeles County, authorities said Tuesday. At a news conference with L.A. County Sheriff Alex Villanueva, California Atty. Gen. Rob Bonta announced the results of the sweep, which targeted hundreds of people listed in a statewide database of those banned from possessing firearms. “When we confiscate an illegal firearm, we aren’t just taking a dangerous weapon off the streets, in the wrong hands. We are preventing the next mass shooting, the next domestic disturbance, the next horrific act of gun violence,” Bonta said. Officials said people who once legally owned guns can be placed in the state database after committing certain crimes, being diagnosed with a serious mental illness, or having a restraining order issued against them. “These guns are not supposed to be in the hands of those who have them because they have been determined by our legal system to be potentially dangerous,” Bonta said.Bonta said authorities closed 439 investigations of people on the list, seizing 55 handguns, 19 rifles, 15 shotguns, 17 assault weapons and eight ghost guns. Thirteen people were arrested.Since state officials created the database in 2006, authorities said they have seized more than 20,000 guns from people legally banned from having them.