This report says the gunman was taken into custody =>
“One person was killed and two others were injured when a gunman opened fire inside a Costco store in Southern California, authorities said. The suspected gunman was taken into custody and hospitalized. Police have not identified him.”
So was it an off-duty cop intervene in some guy busily shooting other people in the store?
I saw several recent articles that said he was NOT in custody, because he claimed self defense and an investigation is ongoing.