A Kentucky sheriff has been arrested after fatally shooting a judge in his chambers, police say.

District Judge Kevin Mullins died at the scene after being shot multiple times in the Letcher County Courthouse, Kentucky State Police said.

Letcher County Sheriff Shawn Stines, 43, has been charged with one count of first-degree murder.

The shooting happened on Thursday after an argument inside the court, police said, but they have not yet revealed a motive.