Residents of isolated Baoxing county were relieved when rescuers reached them, but they are still struggling for necessities.
The roads connecting Baoxing and Lushan county, another badly hit area, were repaired on Sunday night, but landslides are making the journey difficult.
It can take up to six hours to make the 40-kilometre trip.
The hilly terrain also makes it difficult for helicopters to land and one had to abandon its mission due to strong winds.
More than 800 firefighters were sent into Baoxing, travelling by foot and boat.
Workers tasked with restoring electricity supplies and telecommunications were also sent to the county, climbing through mountains up to 4,000 metres high. Residents cheered when the rescue workers arrived, but many are worried about how long their food supplies will last.
Almost all the houses in Lingguan township were damaged and, with rocks blocking roads, residents had to carry severely injured people out of the town for medical treatment.
"The roads have collapsed and we cannot get out," said Baoxing resident Gou Xiaofeng. "The rocks keep blocking the road. We are isolated."
Firefighters used an excavator to dig through the rubble of a collapsed vegetable market in the county, where five people were believed to be buried.
Wrecked cars line the roadsides. One Baoxing resident, Tai Guozhi, was searching for his lost son in the abandoned vehicles. The son, 30, is due to get married.
"My family will fall apart if my son is really dead. I can't think what I am going to do in the future," Tai said.
Many of the victims are living in tents, and a secondary school built in the township after the 2008 Wenchuan earthquake is serving as a temporary shelter.
China National Radio reported yesterday that the county was in urgent need of baby food and formula, with many women unable to breastfeed because they were too tired and scared.
The radio station also reported that there was a lack of basic medicines.
"There is not enough milk and there is no infant formula," said one woman holding her two-month-old daughter. Volunteers said on their microblogs the county did not have enough rice or drinking water.
Social critic Li Chengpeng formed a team of five volunteers to deliver relief aid to the county.
He said on his microblog that the team got to the county by foot and found residents in need of tents, candles and food.
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