The death toll from China's deadliest earthquake in decades climbed to nearly 15,000 on Wednesday, as officials warned of calamities downstream from broken rivers and dams strained to bursting point. Tens of thousands of troops, fire-fighters and civilians raced to save more than 25,000 people buried across a wide swathe of southwest Sichuan province under collapsed schools, factories and hospitals after Monday's 7.9 magnitude quake. Many schoolchildren were buried as they were taking an afternoon nap. One body of a boy was found clutching a pen.