A Warrenton man killed himself after holding a Missouri State Highway Patrol trooper hostage for a brief period at a home in Vichy, according to the Maries County Sheriff’s Department. The man was identified as Clifford R. Karst, 42. Police described Karst as the ex-boyfriend of the female trooper. Her name is not being released. Police said Karst died from a self-inflicted gunshot wound to his head around 4:30 p.m. on Wednesday, July 4. An autopsy conducted the following day confirmed Karst had shot himself, according to Sheriff Chris Heitman. Toxicology results are still pending, he added. Police responded to the trooper’s home after she managed to radio dispatch and following a 911 call made by a neighbor. Prior to police arriving on the scene, she had been held at gunpoint by Karst inside her home. Heitman said it appeared the incident started as a verbal argument and then escalated. “I believe they were breaking up and he was in the process of moving out,” Heitman said. The woman was able to break free and run outside as police arrived at the residence. Following an approximate 15-minute standoff, police said they heard a single gunshot and then found Karst dead inside. The trooper was uninjured in the incident. She was off-duty at the time. Vichy is located on Highway 63 about 10 miles north of Rolla in central Missouri. According to published reports, Karst had been employed with the Missouri State Highway Patrol from 1994 to 2007 until resigning.