The head of Colorado state’s prison system was shot and killed at his home Tuesday night, just hours before the governor signed landmark gun control legislation drafted in response to a series of mass shootings.

Police said Tom Clements, 58, executive director of the Colorado Department of Corrections, was shot once at his home in the town of Monument. The shooting did not appear to be linked to home invasion or robbery, said El Paso County Sheriff’s Department Lieutenant Jeff Kramer.

Officials said they had started a search on Tuesday night, but by Wednesday morning they had not identified any suspects.

“We don’t know if the shooting was random,” Kramer said.

He said investigators were considering the possibility that Clements’ position as head of state prisons could have motivated the shooting.