As noted in the article, not everyone chose to heed the evacuation orders and leave. They might want to watch Dante's Peak. In that movie, it starts with, "In 1993, United States Geological Survey volcanologist Dr. Harry Dalton and his colleague and fiancee, Marianne, attempt to escape an eruption in Colombia. A piece of hot volcanic debris pierces through the roof of Harry's truck, killing Marianne." That might be considered a "lava bomb" in today's story.
Here in Washington state, you cannot make someone leave their home. You may call it a "mandatory evacuation order," but you can only prevent people from returning to their home. The most famous example of this is Harry Truman and the Mt. St Helens volcano eruption of 1980.
If you choose to watch Dante's Peak, note that you should not try to drive through molten lava in an automobile. Not a good idea!