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Amr Nabil, Associated Press
Egyptian book restoration officials surround a vehicle full of burnt and damaged books which were saved from the research center, set up during the three-year occupation of Egypt by France in the late 18th century, in Cairo, Egypt, Monday, Dec. 19, 2011. The building was almost completely gutted by a fire which broke out during the height of the clashes on Saturday, when troops on its roof and on other nearby rooftops hurled rocks down on protesters below.

CAIRO — A field hospital doctor says Egyptian troops and riot police have raided Cairo's Tahrir Square in their latest attempt to evict protesters who want the ruling military to immediately step down.

Ahmed Saad says a 15-year-old protester was in critical condition after suffering a gunshot wound in Tuesday's attack.

It was the second pre-dawn raid in as many days on the city's central square. It comes as Egypt's ruling generals are coming under mounting criticism at home and abroad over the excessive use of force by troops against unarmed protesters, including women, since the latest spate of violence broke out on Friday. Fourteen people have died.

The military took power after an 18-day uprising forced autocratic leader Hosni Mubarak to step down in February.