A teenage gunman killed his grandparents before opening fire at a high school in Thailand, killing five staff members, authorities say. Video from the school sh

A teenage gunman killed his grandparents before opening fire at a high school in Thailand, killing five staff members, authorities say. Video from the school shows abandoned backpacks, shell casings and a classroom left in disarray. [▻](https://video.twimg.com/amplify_video/2085700740324974592/vid…