This seems incredibly unlikely. Anyone with a good machine shop and some fissile material can build a fission bomb in their garage (ok, it's not that easy). B

This seems incredibly unlikely. Anyone with a good machine shop and some fissile material can build a fission bomb in their garage (ok, it's not that easy). But fusion bombs are another beast altogether. Fusion bombs work by setting off a fission primary stage inside a closed container, which ignites fusion in a deuterium secondary stage. But the devil is in the details. The energy from the primary (in the form of either neutrons, heat, or X-rays; which one it is is highly classified) needs to be focused through an interstage (the details of which are, again, classified) into some sort of styrofoam (really) medium which turns into plasma. This somehow starts fusing the deuterium inside it, which involves the use of a fissile "spark plug" to produce more neutrons. And deuterium isn't that easy to come by. The whole process is so tricky that the British couldn't get it to work for a long time after the Americans gave them plans. So, yeah, I don't believe it.