A male teacher at a Catholic school in Plymouth has been fired for sending "inappropriate" e-mails to several female students, and police are now investigating the case.

This is the third time in Minnesota in the past week that a teacher or athletic coach has been accused of crossing boundaries with students, with the previous two involving sexual relationships that have led to felony charges. All three occurred at Catholic schools.

Police say they were notified Wednesday afternoon of the teacher's firing and that "the case is currently under investigation."

A statement from Providence Academy read, "We do not tolerate this behavior, and upon learning of it took immediate action. The safety of our children is our first priority."

School spokeswoman Kelly Mathisen declined to elaborate the statement, including any details on the nature of the e-mails or the approximate ages of the girls. Police have so far only added that the fired teacher is a man and no one has been arrested.

Founded in 2001, Providence Academy is a coeducational school with more than 900 students from pre-K through 12th grade.

Earlier this week, a math teacher at Pacelli High School in Austin was fired and charged with criminal sexual conduct. Mary F. Gilles, 28, is accused of having a relationship with one of her students at the coeducational Catholic school. Authorities said it's possible she became pregnant from the relationship.

Also in recent days, a former varsity tennis coach at the all-girls Visitation School in Mendota Heights was charged with sexual misconduct on suspicion of having a yearlong relationship with a girl on his team. Police are investigating the possibility that he may have victimized others. Daniel Erik Hubbard Wilson, 27, of St. Paul, was charged with first-degree criminal sexual conduct and third-degree criminal sexual conduct.

Staff writer Kelly Smith contributed to this report. Paul Walsh • 612-673-4482