In Afghanistan, the Taliban have been caught, at least 38 times, using white phosphorus (for 80 years used in combat for generating smoke, light and fires) as a weapon. This is illegal, because as a weapon, white phosphorus becomes chemical weapon, which is illegal according to international treaty (which the Taliban have not signed, but no matter.)
White phosphorus creates smoke (to hide troops from enemy view) and light (to illuminate the battlefield) because it burns very hot and fast. The Taliban have obtained 82mm mortar shells and 107mm rockets containing white phosphorus warheads. Both these weapons are of Russian design and are manufactured in places like Russia, China, Pakistan and Iran. The Taliban thus have easy access to these white phosphorus munitions via gunrunners and corrupt soldiers. The white phosphorus warheads are sometimes used as part of roadside bombs, but are more often fired at military or civilian targets. Since white phosphorus causes nasty burns, it is useful in terrorizing civilians. The Taliban has to do this a lot to prevent civilians from telling police where the terrorists are and what they are up to.