A man is in custody after firing inside the store, Lt. Jeff Edwards of the Corona police said. His name wasn't immediately released.The shooting stemmed from an argument inside the store, but the relationship among the victims and the alleged gunman is unclear, Edwards said. Officers found four people "down" inside the Costco store: the suspect, the deceased and two injured people, Edwards said. The slain person was not immediately named. The alleged gunman and others were taken to hospitals, Edwards said.An off-duty Los Angeles police officer was involved in the shooting, according to the Los Angeles police. The officer suffered minor injuries and has been released from the hospital."The Department has initiated an Administrative Investigation and is working with the Corona Police Department to learn more about the incident," Los Angeles police said in a statement.The shooting was not believed to be a domestic dispute, he said. Police weren't looking for anyone else in connection with the crime, they tweeted.
'Emergency' doors wouldn't open, shoppers said
Some people were also injured trying to flee the store, Edwards said.Naveed Navi and Rochelle Flores were shopping for items for a barbecue when gunshots rang out, they told CNN affiliate KTLA. They heard four shots and tried to escape through emergency doors, but they wouldn't open, the pairRead More – Source
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