It doesn't have to be improvised. Some armies have what they call "off-route mines". They are essentially a shaped charge projector coupled with a triggering m

It doesn't have to be improvised. Some armies have what they call "off-route mines". They are essentially a shaped charge projector coupled with a triggering mechanism. If employed by the kind of folks who care about civilian casualties there are smarter triggering mechanism which are unlikely to be triggered by someone walking by, or even driving by in something less heavy than a tank. https://www.youtube.com/watch?v=praws6uM--A https://www.youtube.com/watch?v=praws6uM--A