CAIRO: Protesters and journalists reported security forces in Tahrir Square used teargas that caused many protestors to faint last night November 22. Protestors set fire to piles of garbage, thinking the smoke caused by fire could push the gases into the sky. Doctors in Tahrir Square said they cannot identify the type of tear gas used by security forces. A journalist reported the protestors chanted, “People want to executed Tantawi,” referring to chairman of Egypt's ruling military council Hussein Tantawi. RELATED STORIES: - In Pictures: Tahrir clashes continue for fourth day - Increase in clashes between security forces and demonstrators in Tahrir Square - National committees control Tahrir Square, tension at Mohamed Mahmoud St. - Political powers to discuss Tahrir events' repercussions - ElBaradei slams 'massacre' in Egypt's protests - Renewed clashes between protestors, police in Mohamed Mahmoud - Police use internationally banned gas to disperse demonstrators - 30 dead in Egypt clashes: health ministry - Min of Interior officials summoned over Tahrir clashes - Baradei: Live bullets, nerve agents used against Tahrir protesters - Abu Ismail calls on demonstrators not to leave Tahrir Square