Plastic Surgeon Arrested in Texas Doctor's Death A West Texas plastic surgeon paid someone $9,000 - in the form of three silver bars - to kill another doctor who was dating his ex-girlfriend, police alleged Monday. Dr. Thomas Michael Dixon and David Neal Shepard were arrested by police in Amarillo shortly after midnight, authorities announced. They are suspected of being involved in the death of Lubbock doctor Dr. Joseph Sonnier III. An arrest warrant affidavit suggests a love triangle between Dixon, Sonnier and a woman who was not identified by police. The affidavit alleges Dixon offered Shepard the three bars, each with an estimated value of $3,000, to kill Sonnier, who was chief pathologist for Covenant Health System in Lubbock. Sonnier, 57, was found shot and stabbed Wednesday inside his home in Lubbock, about 120 miles south of the Texas Panhandle city of Amarillo. A window was broken. Sonnier's girlfriend told a police detective that Dixon, 48, was her ex-boyfriend and that he "insisted on seeing her, even though she was dating Dr. Sonnier," according to the affidavit. This photo provided by the Lubbock Police Department, shows Dr. Thomas Michael Dixon, a plastic surgeon who was arrested with David Neal Shepard for murder in Lubbock, Texas. Documents in an arrest warrant suggest Dixon arranged to have Dr. Joseph Sonnier III killed because Sonnier was dating Dixon's ex-girlfriend. Sonnier III was found dead Thursday, July 12, 2012. (AP Photo/ Lubbock Police Department) Close Also, a co-worker of Sonnier told the detective that Sonnier had said that his girlfriend's ex-boyfriend "would not leave her alone," the affidavit says. Meanwhile, police discovered through an online database that Shepard had sold a 100-ounce bar of silver at an Amarillo pawn shop for $2,750, the affidavit says. His roommate told authorities that Shepard had been watching Sonnier for weeks and texting Dixon. Shepard told his roommate that he broke into Sonnier's home through a window and shot him several times with a gun Dixon had given him, the affidavit said. He knew several details that investigators had kept private, it said. Shepard, 51, tried to commit suicide in the days after the murder by cutting his wrists, the roommate allegedly told authorities. The roommate said Dixon closed the wounds, told him to calm down and "suggested that David Shepard leave for a couple of weeks," the affidavit said. Lubbock Police Capt. Jon Caspell said Monday that he didn't know when Dixon and the woman broke up. Dixon and Sonnier appeared to have known each other aside from the woman, Caspell said. Dixon is a well-known plastic surgeon in Amarillo. No one answered the phone Monday at his practice, High Plains Plastic and Reconstructive Surgery. He was transferred from Randall County to the Lubbock County jail on Monday afternoon. Online court records did not yet list an attorney for him. No phone number was listed for Shepard.