The posts on Louis Freeh
and the WP shells
have reminded me of the massacre-by-fire at Waco.
After that fiasco, the FBI admitted
it used two "pyrotechnic" devices during the initial stage of its assault on the Branch Davidian compound. The fire which killed many of the Branch Davidians started several hours later and was supposedly not related to the use of these devices.
The real scandal was the FBI repressing the fact they had used anything capable of starting a fire. Fortunately the Texas Rangers had possession of the evidence, and they allowed a documentary-maker to photograph two canisters later identified as 40mm M651 CS grenades
. I can't find a site on the Internet describing the incendiary material used in these grenades, but it is presumedly WP or Magnesium.