OSHKOSH, Wis. (AP) — Wisconsin high school resource officers have found themselves on the front lines in two student shootings in the past two days, underscoring how police in schools can face life-or-death situations and likely adding to the debate over the best ways to respond to school threats.

An Oshkosh Police Department resource officer shot a 16-year-old student Tuesday after the boy stabbed him in the officer’s office at Oshkosh West High School. A day earlier, a resource officer at Waukesha South High School helped clear students out of a classroom after a 17-year-old student pointed a gun — it turned out to be a pellet gun — at another student’s head. Another police officer entered the room and shot the student. No one in either incident suffered life-threatening injuries.

ì“Today’s tragic event shows that trained school resource officers can save lives,”î Oshkosh Superintendent Vickie Cartwright said at a news conference.

The debate about the role of armed teachers or police in schools has been a constant in the wake of school shootings across the country. But rarely have armed resource officers been able to prevent a shooting.

An estimated 43% of public schools have armed officers on campus, according to a survey by the National Center for Education Statistics. The survey covered the 2015-2016 school year, the most recent year surveyed. That figure doesn’t include schools with armed private security guards or teachers and administrators who carry guns.