The school where I teach physics with the Peace Corps in Guinea, West Africa differs from American schools in many respects. We have no electricity, no running water, no computers. Teaching materials are sparse, and many of my students walk miles to school. Yet some features feel the same: the familiar buzz of learning, the chatter of the kids as they arrive and leave each class, the sense of safety and innocence in the classroom, the feeling of community in a school that nurtures the future in this quiet, remote village.

It was a typical Wednesday, the day we were attacked. We gathered at 7:45 am for the flag raising in the central courtyard surrounded by the concrete school buildings. The principal, Mr. Pegaidy, made an announcement thanking the students and teachers for showing up at school even though in other parts of the country the teachers and students were on strike. Teachers in Guinea, like those in many parts of the world, are overworked and underpaid. Teachers and students had been protesting, pressuring the government for more money. The schools in my village, however, had not joined in the strike, and Mr. Pegaidy was proud that classes were in full swing.

My eighth-grade class of around 70 students began with a discussion about how to calculate the density of objects. Suddenly there was a loud cracking sound. We all paused.

I had no idea what this noise was, but it came from above and was frighteningly loud. It made the building shake. “Bang!” Again. And again.

The sound echoed loudly on the tin roof. (During the rainy season, it is often too loud to teach). My mind raced. What could possibly have fallen from such a tall tree? What strange hailstorm had arrived in our 80-degree weather?

The rapid-fire sounds came closer together, and the kids jumped to their feet, charging the door en masse, crowding each other to run outside to the courtyard. A few students warned, “We should not go outside!” so we locked ourselves inside and rushed to a corner farthest from the windows that face the courtyard. We tried to escape through a window on the other wall that faces a field, when a stone nine inches long flew past and landed right outside. That’s when I realized that the incessant pounding was coming from large rocks thrown at our classroom from the courtyard.

I looked up at the high ceiling. It seemed sturdy enough to withstand the pounding, but I wondered what would happen if it were to crack. Rocks began hitting the locked door, and concrete dust burst off the walls from the strength of the blows.

A rock flew through the window, a stray bullet of sorts. I imagined how it would feel if instead of rocks those cracking sounds were rounds of gunshots. Bullets, rather than rocks, flying in every direction, raining on the flimsy roof. The closest clinic with any semblance of modern medical care is more than 10 hours away over a challenging rutted road, if you can find a car. I felt grateful that none of my students could possibly afford a gun, and that any gun here would be low tech and obsolete, likely to jam or misfire.

The students huddled close, peeking out the windows and shaking their heads at their peers who had joined in the mayhem. Finally, attention seemed to turn away from the building where I teach, and we heard the crowd outside move across the large courtyard toward the administrative office. In the suddenly eerie quiet surrounding our building, the students and I rushed out of the classroom and sprinted away from the school area.

From a safe distance we looked back, and I finally saw the full picture of the melee. Around 75 teenagers in their student uniforms were throwing rocks at the school buildings and the administrative office, and no one could get them under control. The mob had far more power than the few teachers, and I fought the urge to run back to help my colleagues. As a Peace Corps volunteer I am forbidden from intervening in situations like this, not only for my own safety, but also to preserve the role of the Peace Corps as an apolitical development organization. Frustrated and worried, I wondered if any of the teachers or students I’ve come to love were injured.

I later learned that the violence erupted from a poorly organized student protest that arose from legitimate concerns. A few students began throwing stones and, fueled by the mob mentality and the exuberance of adolescence, others joined in, and the situation spiraled out of control. Rocks were easily available, and the angry crowd put them to use, knocking holes in the ceilings of the administrative building and some classrooms. But no one was injured.

What a different story this would be if the student demonstrators—and the teachers, for that matter—had access to weapons like the AR-15, which was designed for U.S. soldiers to efficiently massacre the enemy. I shuddered at the thought, as I read the report of a radiologist who treated victims from the tragic Parkland shooting, describing how wounds caused by AR-15s are dramatically more damaging than those caused by typical handguns, let alone rocks.

As the first Peace Corps volunteers to return to Guinea following the Ebola crisis, my colleagues and I have faced many public health challenges in Guinea, from Ebola to malaria to the lack of clean water or traffic regulation. But we are free from one growing public health crisis raging in America—the epidemic of gun violence. Yes, stones can kill too. I feared for my students’ safety while we huddled in the classroom, and I feared for the students who, carried away in the heat of the moment, rushed outside to join their peers in throwing rocks. But how different would the outcome have been if these students had easy access to military grade American rifles. As Nicholas Kristof notes, “people all over the world become furious and try to harm others, but only in the United States do we lose one person every 15 minutes to gun violence.”

Some argue that people with the intention to harm will find a tool with which to do it. I’ve seen the meme circulating on Facebook, juxtaposing a rock with an assault rifle. “Cain killed Abel with a rock. It’s a heart problem; not a gun problem.” Jeremiah 17:9.

As a teacher in a school that was recently attacked by an angry mob armed with rocks, I have to say: guns are definitely different from rocks.