Rescuers continued to pull some victims out of the rubble two days after the quake, but state media said tens of thousands more were still trapped.
Government officials said rescuers who hiked to the city of Yingxiu in Wenchuan county -- at the epicenter of Monday's magnitude 7.9 earthquake -- found it "much worse than expected," quoted the Associated Press.
Roads leading to the county were still being cleared of debris following the temblor. Aid stations and refugee centers were popping up over the disaster area the size of Maryland, reported the AP.
The death toll in the city of Mianyang was confirmed at 5,430, up from 3,629, on Wednesday, with more than 18,000 people still thought to be buried, according to the Xinhua news agency.
A middle school in Sichuan province's Qingchuan county, where children were taking a noon nap, collapsed in the quake, killing 178 children with 23 still missing, Xinhua said.
Storms that had blocked flights to some of the worst-hit areas finally cleared on Wednesday. Helicopters and trains carried food, drinking water, tents and military personnel to damaged areas, the AP reported.
Aid pledges were rolling in, from inside and outside China. The Chinese public donated 877 million yuan ($125.4 million), said the Ministry of Civil Affairs, according to Reuters.
The Hong Kong government pledged $38 million, Macau: $14.3 million, and Taiwan: $6,450, along with plans to provide search teams.
The United States pledged $500,000 as an "initial contribution". Japan provided $4.8 million in cash and goods. Russia sent a plane carrying 30 tons of relief materials -- the first international aid delivery to China -- with another 100 tons of goods en route.
South Korea offered $1 million, Thailand: $500,000, and Singapore: $200,000, Reuters reported.