Today The Guardian is reporting on a new US Army “non-lethal personal suppression projectile”

Not many details are known about the classified weapon, but the article speculates:

“Experts suggest three possible payloads: an existing riot-control agent, malodorants or a new chemical agent. Existing agents include CS gas and a form of pepper spray. But these seem unlikely choices, because their effects only last minutes, and could wear off before friendly forces arrive. They could also face a legal challenge: the 1997 Chemical Weapons Convention prohibits the use of riot control agents in warfare.”