Los Angeles City councilmembers Aug. 3 introduced a motion to ban the purchase and possession of ghost guns in the city.   Ghost guns, also known as kit guns, are sold as partially assembled guns that can be completed using purchased parts. The unfinished parts are not legally required to have serial numbers or a background check to purchase and are often sold at gun shows or online.   Councilmembers Paul Koretz and Paul Krekorian requested an ordinance banning the possession, purchase, sale, receipt and transportation of all frames, receivers and firearms that are unfinished and non-serialized in the city.   Koretz said in a statement that shootings and homicides have increased 30 percent since the start of the COVID-19 pandemic. Shootings are up 43 percent, he said, with over 40 percent of guns confiscated by the ATF and a third of crime guns recovered by the LAPD in Los Angeles were ghost guns last …