For reasons that are still unclear the U.S for some time has been exporting tear gas to Chinese police in Hong Kong. Earlier this month, a Buzzfeed News investigation uncovered that in piss-poor conditions American workers are making the gas and then exporting it to China where it is actively being used against protesters.
The United Nations' Commissioner on Human Rights recently condemned Hong Kong following the initial revelations. Buzzfeed discovered that the shipments were being fired into crowds; residential areas, and even directly at protesters. Videos have for months surfaced online and on various forms of Chinese social media.
Via Buzzfeed News