A former high school English teacher in Montezuma who was charged last year with inappropriate sexual contact with four students now faces more charges.

This past June someone told authorities 28-year-old Derek John Bates had committed sexual acts with two more students. These incidents allegedly occured two years ago, during the spring and early summer of 2012. Authorities interviewed the two students, who said the incidents occured off of school grounds. Bates was arrested Friday and charged with two counts of sexual abuse in the third degree and one count of sexual exploitation by a school employee.

Bates had been a teacher at the school from the fall of 2009 ’til October of 2012 when he resigned after being charged with drinking alcohol in a classroom with a 17-year-old student. Last summer Bates was charged with third degree sexual abuse and other sex-related charges based on the testimony of four other students.

Radio Iowa