Rescuers picked through the rubble of collapsed homes, schools and office towers, searching for survivors of a massive earthquake that has killed almost 12,000 people in China. - But the death toll from Monday's quake could skyrocket, as an estimated 18,000 people remain buried under debris in the city of Mianyang in the hard-hit Sichuan province, Xinhua, the country's official news agency, reported. - At least 3,629 have been found dead in the city of about five million, and it's unclear if these numbers are part of the death toll of 11,921 people, a toll compiled by the Chinese government. - Xinhua said military search teams on Tuesday were only just reaching Wenchuan, the mountainous county in the southwestern province of Sichuan where the epicentre of the 7.9 magnitude earthquake was located. - The county, with roads blocked by debris and washed out by heavy rain and landslides, was almost inaccessible, Xinhua said. One team of military...