A surgery in May that left a man complaining of persistent back pain appears to have led to the USA's latest mass killing at the St. Francis Health System campus in Tulsa, Oklahoma. Tulsa Police Department Chief Wendell Franklin identified the four people killed killed Wednesday as Dr. Preston Phillips, Dr. Stephanie Husen, a receptionist and a patient. Franklin said the gunman had had surgery recently and targeted Phillips, who performed the surgery. According to Franklin, Dalgleish and other Tulsa police, here's how events transpired. ➡️