A Kentucky sheriff has been arrested Thursday in connection with the fatal shooting of a district judge inside a courthouse, Kentucky State Police said.

Police have a suspect in custody after a district judge was killed at the Letcher County Courthouse in Whitesburg, Kentucky, officials said.

KSP’s preliminary investigation indicates that Letcher County Sheriff Shawn Mickey Stines, 43, shot Mullins following an argument inside the courthouse. They say Stines was taken into custody at the scene without incident. Stines has been charged with one count of first-degree murder.