A 31-year-old Niagara Falls high school teacher is facing a number of sex-related charges stemming from alleged incidents involving two female students.

According to Niagara police, the charges relate to an investigation launched in December focusing on allegations of “inappropriate sexualized behavior” by a teacher at A.N. Myer Secondary School.

The victims were both under the age of 18 at the time of the alleged incidents, police said.

“Detectives determined that one of the girls was a student at A. N. Myer Secondary School where the teacher taught from 2013 (until) the commencement of this investigation,” police said in a release issued Monday afternoon.

“The second girl was a student of Sir Winston Secondary School in St. Catharines, where the teacher taught from 2009 to 2013.”

The charges stem from alleged incidents both on and off school property, and before and after school hours.

Michael J. Molnar, of Pelham, is charged with two counts of sexual assault, sexual interference, invitation to sexual touching, and sexual exploitation.

He is schedule to appear in court in St. Catharines for a bail hearing Tuesday.

Anyone with information is asked to contact police at 905-688-4111 ext. 5100 or Crime Stoppers at 905-222-TIPS (8477).