A protestor throws stone towards the office building of the Roads and Bridges Authority in Cairo, Egypt, Dec. 16, 2011. At least two people were killed and 222 others injured in the latest clashes between protestors and security forces on Friday in Cairo, said the health ministry. [Photo by Li Muzi/Xinhua]

Protestors gather in the smokes in front of the burning office building of the Roads and Bridges Authority in Cairo, Egypt, Dec. 16, 2011. At least two people were killed and 222 others injured in the latest clashes between protestors and security forces on Friday in Cairo, said the health ministry. [Photo by Li Muzi/Xinhua]

A protestor stands in front of the burning office building of the Roads and Bridges Authority in Cairo, Egypt, Dec. 16, 2011. At least two people were killed and 222 others injured in the latest clashes between protestors and security forces on Friday in Cairo, said the health ministry. [Photo by Li Muzi/Xinhua]

A protestor walks past the burning office building of the Roads and Bridges Authority in Cairo, Egypt, Dec. 16, 2011. At least two people were killed and 222 others injured in the latest clashes between protestors and security forces on Friday in Cairo, said the health ministry. [Photo by Li Muzi/Xinhua]

A protestor gestures to the police on the office building of the Roads and Bridges Authority in Cairo, Egypt, Dec. 16, 2011. At least two people were killed and 222 others injured in the latest clashes between protestors and security forces on Friday in Cairo, said the health ministry. [Photo by Li Muzi/Xinhua]

A protestor smashs a brick in front of the office building of the Roads and Bridges Authority in Cairo, Egypt, Dec. 16, 2011. At least two people were killed and 222 others injured in the latest clashes between protestors and security forces on Friday in Cairo, said the health ministry. [Photo by Li Muzi/Xinhua]

A protestor stands in front of the burning office building of the Roads and Bridges Authority in Cairo, Egypt, Dec. 16, 2011. At least two people were killed and 222 others injured in the latest clashes between protestors and security forces on Friday in Cairo, said the health ministry. [Qin Haishi/Xinhua]

Protestors clash with security forces in Cairo, Egypt, Dec. 16, 2011. At least two people were killed and 222 others injured in the latest clashes between protestors and security forces on Friday in Cairo, said the health ministry. [Photo by Qin Haishi/Xinhua]

A protestor throws stone towards the office building of the Roads and Bridges Authority in Cairo, Egypt, Dec. 16, 2011. At least two people were killed and 222 others injured in the latest clashes between protestors and security forces on Friday in Cairo, said the health ministry. [Photo by Qin Haishi/Xinhua]

Protestors clash with security forces in Cairo, Egypt, Dec. 16, 2011. At least two people were killed and 222 others injured in the latest clashes between protestors and security forces on Friday in Cairo, said the health ministry. [Photo by Qin Haishi/Xinhua]

Protestors clash with security forces in Cairo, Egypt, Dec. 16, 2011. At least two people were killed and 222 others injured in the latest clashes between protestors and security forces on Friday in Cairo, said the health ministry. [Photo by Nasser Nouri/Xinhua]