Here are some excerpts from an article at wired.com:
The Pentagon has a new secret weapon to neutralize sites containing chemical or biological weapons: rocket balls. These are hollow spheres, made of rubberized rocket fuel; when ignited, they propel themselves around at random at high speed, bouncing off the walls and breaking through doors, turning the entire building into an inferno. The makers call them "kinetic fireball incendiaries." The Pentagon doesn't want to talk about them, but published documents show that the fireballs have undergone tests on underground bunkers.It sounds like one rocket ball would replace a dozen or so plastic spheres. But you'd have to be sure and drop them a long distance from the fireline. And, if one went off inside a helicopter, it would be game over.
There are plenty of bombs which could destroy a lab, and bunker-busting weapons can tackle hardened underground facilities. But blowing up weapons of mass destruction is a not a good idea. Using high explosives is likely to scatter then over a wide area, which is exactly what you want to avoid.
Each fireball is a hollow spherical shell with a hole in it; when the inside is ignited, the hole acts as a rocket nozzle. The kinetic fireballs eject an extremely high-temperature exhaust which will heat up the surrounding volume to over 1,000 F within seconds. Their random ricocheting around ensures that they will fill any space they occupy, and they are capable of diffusing throughout a multiroom structure.