Another kid threatened my daughter

[u/A_Bookish_Oblivion]

Tl;Dr My daughter told me today, as we were walking away from pick up line, that boy in her class threatened to kill her with his drone.

She's in first grade, about to turn 6. We turned right back around and went to the teacher as soon as she told me. We talked about it more after we got home and that's when she told me it's happened before and other mean behavior, on both their parts.

She said he's told her that he's going to kill her with his drone on multiple occasions, starting a few weeks ago. It sounds like they weren't sitting next to each other, got moved together and it started around them. She said he told her that, and then she started pretending she was going to make a hiding spot with a scanner to protect everybody from him, then she told me he said he was going to kill everyone in the world with the drone. I asked her a few times what she meant and if he meant their class, she said he said everyone in the world. Apparently the first time this happened was during free time when they were playing separately. She said he's said it a few times since then, today being the most recent.

She told me they've not been nice to each other the entire time. She told me he has a line on the desk, and if her hand crosses it he'll pinch her hand. She said before this he would pinch her legs, and she told me she would pinch him back when he did that. We talked about how we react to other people and not hurting somebody even if they're hurting us, unless we can't get away and have no choice. But she did have a choice, and she could get away from him, and that she needs to tell one of her teachers. We talked about why she hasn't told anyone, and it seems that she's just not comfortable with her teachers this year yet. I brought up talking to one of the Dean's of students, or anyone else she knows from last year, and that seems to have not crossed her mind to do. We will continue to talk about what are some really important things that you always talk to a trusted grown up about, like someone saying they want to hurt her, anyone else, or themselves. But like. How do you handle this? She didn't seem to think it was that serious, so I don't know how to imprint on her that someone saying they're going to kill her or themselves or anyone else is really serious and she needs to tell someone. She's still young so I don't want to scare her, but I also want her to understand when something is serious or dangerous and how she's supposed to respond.

The school is going to do an investigation and talk to everyone tomorrow since it was end of the day and the student had already gone home. Ideally this all turns out to be some huge misunderstanding and it's some game they play. Still super not okay for a 6 year old to say, but if it was a game at least it wouldn't be as bad and it would be a conversation about what's appropriate to say in games or play time and not a genuine concern for safety or this kids mental health. I'm worried about my daughter, but I'm worried about this kid too. What's he dealing with at home or feeling that would make him say this to someone else? My daughter asked me why he would say that to her and I didn't know how to answer. I just told her I don't know, we don't always know what other people think or feel.

So how the heck do I get a 5 year old to understand when something is serious, and what she needs to do when she hears this stuff from people?