JIANGYOU, China (CNN) -- Rescuers struggled to reach some of the hardest-hit areas of southwestern China on Tuesday after a massive earthquake that left a death toll well above 12,000.
Rescuers found at least 500 dead in the Chinese district at the epicenter of the magnitude-7.9 earthquake Tuesday. But heavy rain, collapsed bridges and damaged roads complicated efforts to get troops and aid workers to the worst-hit towns. The rain drove some people back inside homes even as more aftershocks rattled the region, witnesses reported.
The Monday afternoon quake's epicenter was in the county of Wenchuan, Sichuan province, about 1,500 km (960 miles) southwest of Beijing.
The state-run news agency Xinhua reported the death toll at more than 12,100 before Tuesday's latest reports, with more than 26,000 injured, 7,800 missing and more than 9,400 trapped beneath debris.
During a visit to a school in Shifang, where more than 100 children were trapped beneath rubble, Chinese Premier Wen Jiabao promised that saving lives was a top priority. Look at photos of China confronting the quake devastation »
"We will put our best efforts forward to save all those alive who can be saved," he said. "This disaster has all tested us. We all have to band together and have confidence and push forward."
Wen also visited a stadium in the city of Mianyang, where more than 10,000 earthquake victims have been temporarily resettled, Xinhua reported.
"The transportation of food must be faster," the news agency quoted him as telling government officials. "Children are short of food."
Hundreds of soldiers and disaster workers descended on Wenchuan, many of them digging by hand, according to the disaster relief headquarters of the Chengdu Military Area Command. Soldiers said that only 3,000 of the town's 12,000 residents survived the quake. Watch as dazed, bruised survivors battle the elements »
More than 70 percent of the town's roads were damaged, and almost all bridges had collapsed, the soldiers reported.
China is no stranger to natural disasters: A 1976 earthquake killed more than 250,000 people. But analysts said the Chinese response to Monday's quake has been the most transparent of any disaster, with state media frequently updating casualty tolls and deploying troops rapidly to the worst-hit areas.
Gareth Leather, an analyst for The Economist magazine, said the communist government was criticized for its response to the 2002 outbreak of severe acute respiratory syndrome.
"The government was very secretive about it, which in turn allowed the disease the spread across China and Asia a lot quicker than it otherwise would have done," Leather said. "This time they have been very open about it, which I think is maybe showing signs that lessons have been learned." Watch quake victims pulled out of rubble »
Li Chengyun, vice governor of Sichuan, said that about 3.5 million homes were destroyed in the province. David Jones, an English teacher in the city of Chengdu, said residents were camping out on riverbanks, in parking lots and other open spaces despite "terrible" weather.
"People are doing everything they can to stay outside," he said. "In a lot of cases, they can't return to their buildings."
He said survivors were lining up to donate blood and remained calm, though appeared "extremely tired." Grief is spreading as the scope of the disaster is realized »
"The people here have been really helpful to each other, making sure everybody has supplies," he said. "I haven't seen any price-gouging. The mood here has gone from shock, fear, to tiredness." Look at a photo wall of the destruction and rescue efforts »
Wenchuan is the refuge for much of China's panda population, and the State Forestry Administration said the 67 captive pandas among the more than 130 pandas in the Wolong Giant Panda Reserve were unhurt. However, the pandas' caregivers were worried about their supply of bamboo leaf, their main source of food.
In other developments Tuesday:
CNN correspondents John Vause and Paula Hancocks contributed to this report.