Follow KDKA-TV: Facebook | Twitter

SLIPPERY ROCK, Pa. (KDKA) — State police have charged a Butler County teacher with allegedly inappropriately touching four students during class.

Investigators say 51-year-old Robert Willison is a math teacher at Slippery Rock Area Middle School. The district has suspended him.

According to police, Willison is accused of inappropriately touching four female students on four separate occasions. The alleged incidents happened in class.

Willison is charged with institutional sexual assault, indecent assault, endangering the welfare of a child, corruption of minors and harassment.

Willison is scheduled to appear before a judge on Friday.

Stay with KDKA for the latest on this developing story.