hundreds of tools to build ieds found in the couple's garage and key point for investigators is a remote control toy car parts. this is a signature idea in yemen. there is a how-to guide to build bombs using toy car parts for the detonator. it can be set off with the controller using line of sight or an app on your cell phone. the sheer number of devices suggest some training and familiarity with explosives even though this device found near the scene did not detonate. >> it's my understanding that somehow there was three pipe bombs attached together. somehow attached to this remote control car and designed that the remote control device would somehow trigger or set that device off. we don't know if they attempted to do that and it failed or what the story is. >> the fbi says the brothers built pressure cooker bombs using the inspired recipe and