A man may face charges after he reportedly shot and killed another man Monday morning in the parking lot of a Walmart. Police detained the 70-year-old man for questioning at around 7 a.m., shortly after the shooting outside the store on Southeast Military Drive near Roosevelt Avenue. He had been in his truck in the parking lot when he got into an argument with a possibly homeless man in his 30s. Police say the older man shot the other man twice, and he died at the scene. Officers say the shooting may have been in self-defens