There were clashes between demonstrators and security forces in Mohamed Mahmoud St., Mansour and Bab El Louk in Cairo. Central Security Forces (CSF) tried to protect the area. Demonstrators attempted to control the entrances into Tahrir Square by throwing stones at security services, who retaliated with a new type of teargas with stronger effects according to doctors in the field hospital. Teargas was eventually thrown in the centre of Tahrir Square, which remained peaceful until the chairman of Egypt's ruling military council Hussein Tantawi's speech. A group of youth tried but failed to form a human wall between the demonstrators and security forces in the continuing clashes. A number of demonstrators formed groups over the last few hours to clean Tahrir Square and collect garbage. While the number of street vendors increased significantly, there were particular sellers of medical masks and protective goggles. The people's committees were at the entrances of the square, which continued to search people entering the square to make sure they had no weapons. The field hospitals in Mohamed Mahmoud and Bab el Louk also continued to receive those who were injured in the clashes. According to doctors at the field hospitals, the Ministry of Health ambulances transferred dozens of wounded to hospitals of Ahmed Maher and Qasr Al-Aini over the past few hours. They also noted the new teargas used by central security forces is much stronger than what was used in the Egyptian January 25 Revolution and responsible for the many cases of asphyxiation and fainting.