IDA GROVE, Iowa — A former Iowa substitute teacher and coach has pleaded not guilty to having sexual relationships with students at two northwest Iowa high schools.

The Sioux City Journal reports ( ) that 33-year-old John Tietsort, of Battle Creek, Iowa, entered the plea Monday in Ida County District Court to two counts of sexual exploitation by a school employee and three counts of lascivious conduct with a minor.

Prosecutors say Tietsort had a sexual relationship last October through June with an 18-year-old female student at Odebolt-Arthur and Battle Creek-Ida Grove High School, where Tietsort was a substitute teacher and assistant football coach. Tietsort is also accused of having a sexual relationship earlier this year with a 17-year-old female student from Maple Valley-Anthon Oto High School, where Tietsort also was a substitute teacher.

Information from: Sioux City Journal,