See the image caption? It's the name of the reporter, which means it's her image. There's no mention of a license, which means she didn't care enough to let other people use the image (she probably wouldn't care if we do). You can ask her if you want to use this exact image to publish.
One thing you can do is use images off Wikipedia. They're all either public, or have a license allowing for use. There might be similar images of the same school there, because there would defintely be a page for the incident that article is about.