It was not known if the miners were dead or alive, but authorities were hoping for the best until they learned otherwise, said Wang Dexue, deputy chief of the government's work safety department.
"We have had the miracle in the past that a miner was found alive after being trapped underground for 21 days," Wang told a news conference in Beijing. "We are carrying out rescue work on the assumption that they are still alive. We absolutely will not give up."
The 24 miners were trapped in three mines in Sichuan province, Wang said, without giving further details. Sichuan bore the brunt of the quake on May 12 that has caused China's greatest disaster in three decades.
Premier Wen Jiabao returned to the quake zone on Saturday, and hosted U.N. Secretary-General Ban Ki-moon in a visit to one of the hardest-hit towns.
The State Council, China's Cabinet, said the latest confirmed death toll for the quake was 60,560 and listed 26,221 people as still missing.
Wen warned the toll could go much higher, suggesting the government may be giving up hope of finding alive those who are missing.
"It may further climb to a level of 70,000, 80,000 or more," Wen told reporters in the badly damaged town of Yingxiu near the epicenter of the disaster.
Ban, who came to China directly from another Asian disaster zone - cyclone-stricken Myanmar
- promised that the United Nations would help with reconstruction and was waiting for China's assessment of what it needed.
"If we work hard, we can overcome this," Ban said, with Wen standing at his side. "The whole world stands behind you and supports you."
A Chinese military officer took Ban on a tour of Yingxiu.
Some 4,800 of the town's 18,000 people were killed and another 4,000 were still missing, the officer told Ban. Most of the buildings in the town collapsed and those still standing were badly damaged. Reporters could see government workers in hooded white protective suits spraying disinfectant on the rubble.
Meanwhile, experts searched for 15 radiation sources buried in the rubble and survivors moved out of possible danger areas downstream from rivers dammed by landslides.
With their water pooling, the blocked rivers could breach the earthen barriers
- a danger that would grow with coming rains or aftershocks.
Relief workers grappled with getting tents, food and medical care to the displaced. Wen said that the government needed 900,000, tents that and it urged Chinese manufacturers to make 30,000 a day.
The Environmental Protection Ministry said experts from its National Nuclear Safety Administration were trying to contain 15 unspecified "sources" of radiation.
Some 50 potential radiation sources were buried by the quake, Environment Vice Minister Wu Xiaoqing said Friday in Beijing. While 35 have been secured, 15 remained buried under buildings and houses and, though located, were inaccessible, he said.