A man who blamed his surgeon for ongoing pain after a recent back surgery bought an AR-style rifle hours before opening fire at a Tulsa medical office, killing the surgeon and three other people before fatally shooting himself, police said Thursday. Tulsa Police Chief Wendell Franklin says the gunman had recently undergone back surgery and had called a clinic repeatedly complaining of pain. Franklin says the doctor who performed the surgery, Dr. Preston Phillips, was killed Wednesday, along with another doctor, a receptionist and a patient. “We also have a letter on the suspect, which made it clear that he...