http://www.guardian.co.uk/world/2011/nov/21/tahrir-square-us-teargas-used-egypt?newsfeed=true"The teargas used by interior ministry troops in Cairo's Tahrir Square is supplied by a US company. Demonstrators say cartridges retrieved from the scene are branded with the name and address of Combined Systems Inc (CSI).
The firm is located in Jamestown, Pennsylvania. It specialises in supplying what it calls "crowd control devices" to armies and "homeland security agencies" around the world. It also manufactures lethal military equipment.
...The export of teargas to foreign law enforcement agencies is not prohibited. CSI has also sold teargas to the Israeli police, where it has been deployed against Palestinian demonstrators, as well as, reportedly, to the regime of Tunisia's ousted dictator Zine El Abidine Ben Ali. Nevertheless, the revelation that people are being gassed and hurt by US-manufactured projectiles is embarrassing for the Obama administration.
"We have seen the illegitimate and indiscriminate use of teargas," Heba Morayef, a researcher with Human Rights Watch in Cairo, said, of Egypt's most recent street protests, as well as the original revolution in February. "There are a few cartridges from Italy but the vast majority are from the USA."