Students read books for the upcoming senior high school entrance exams after an earthquake in Mianyang, Sichuan province May 12, 2008.
A view shows a collapsed building after an earthquake in Dujiangyan, Sichuan province May 12, 2008.
People search for victims in the debris of a collapsed building after an earthquake in Dujiangyan, Sichuan province May 12, 2008.
People prepare to spend the night in the open air on a street in Mianyang, Sichuan province, after an earthquake hit the area May 12, 2008.
A woman survivor tries to escape from the debris of a collapsed building after an earthquake in Dujiangyan, Sichuan province May 12, 2008.
Rescuers search for students in the debris of a collapsed building at Juyuan Middle School in Juyuan Township of Dujiangyan, about 100 kilometres from the epicenter of an earthquake in Wenchuan county, Sichuan province May 12, 2008 in this picture distributed by China's official Xinhua News Agency
Local residents sleep on the streets after an earthquake in Mianyang, Sichuan province May 12, 2008.
A rescuer searches for victims at the collapsed site of a school building after an earthquake in Chongqing municipality May 12, 2008.
17点14分,都江堰往汶川方向道路被山顶滚落的巨石阻断,车辆无法通过,路人试图翻越巨石堆
17点38分,一市民背着受伤的女友走过倒塌的建筑
17点36分,都江堰市区一建筑起火冒烟,据称有一人被困在六楼
18点36分,幸存少年从废墟中抢救出生活物资
12日下午,在突如其来的地震中,都江堰市聚源镇中学一栋教学楼垮塌,部分学生被埋,至12日19时56分,记者在都江堰市聚源镇中学事故现场发现,死亡人数已增至50余人。当地有关部门正在紧急抢救。