Continual aftershocks and insufficient relief supplies are hampering the rescue efforts in southwest China's Sichuan, 36 hours after a powerful tremor hit the province.

The latest statistics showed that at least 186 people have been confirmed dead and more than 1.5 million affected as of Sunday night, according to the provincial relief authorities.

Rescuers are racing against the "critical first 72 hours after the disaster" to comb the quake rubble and reach every household in the epicenter of Lushan and its neighboring counties affected by a 7.0-magnitude earthquake that jolted the city of Ya'an early Saturday.

Over 1,700 aftershocks have been monitored in Lushan as of 10 p.m., with the strongest measuring 5.4-magnitude, making the already ramshackle houses even more dangerous and the rescue efforts more life-threatening.

A rescue excavator plunged off a 300-meter deep cliff in the morning in Ya'an's quake-hit Baoxing County. The number of casualties have remained unknown as of Sunday night.

"Lifeline" resumes

As of 5 p.m., traffic has resumed on the road linking Baoxing to its neighboring counties of Lushan and Xiaojin and the City of Dujiangyan, resuming transportation of the stranded relief supplies to the county after its 33 hours' post-quake isolation, according to the Sichuan Provincial Department of Transportation.

The road is dubbed as the relief "lifeline" by rescuers.

Several rescue teams managed to reach Baoxing, which has a population of 60,000 and had remained hard to to access after the quake. At least 26 locals have been confirmed dead with another 2,500 being injured as of Sunday morning, according to county head Ma Jun.

"The top priority is to save lives," said Ma. "Meanwhile, we'll resettle the residents and reopen roads."

Altogether 40,000 homeless Baoxing residents are waiting to be relocated as most houses in Lingguan Township and Daxi Village in the county have suffered damage.

Airborne remote sensing images showed that more than 60 percent of buildings in the county seat had suffered damage.

Power supplies have been restored in only a few villages in Baoxing, the most part of which is still shrouded in darkness.

Dire need

Quake survivors in Lushan County are in urgent need of water, food and tents. Xinhua reporters witnessed that residents were waiting for relief goods along the roads linking remote mountain towns in Lushan. Children held up cardboard describing their distress. "500 people, no food, no water, no tents," read a paperboard.

"I had no food for a whole day," said a resident in the Wangjia Village of Longmen Township in Lushan.

The villager was queuing for mineral water dished out by Chen Guangbiao, a high-profile Chinese philanthropist.

Chen said he distributed 1,000 quilts and 1,000 kg of bread while promising to raise 2.3 million yuan (372,337 U.S. dollars) for the quake-stricken region.

But, many of the villagers still gathered at the road near the gate of the village, waiting for the arrival of the rescue teams, as all their food had been buried in the debris.

In the Zhongli Township, 20 km north of the Ya'an City proper, local villagers have set up make-shift tents with any possible materials at hand.

In Baoxing, many local residents spent the night outdoors, in short of food, water and clothing, as there were not enough tents for every family and people were afraid of returning to their ramshackle homes to get supplies amid constant aftershocks.

Chinese Premier Li Keqiang on Sunday urged the country's railway and transportation departments to make every effort to facilitate the entry of tents, quilts and other materials into the quake-hit area.

With resumed traffic and eased traffic jams on more roads, relief supplies are reaching an increasing number of the needy survivors.

The survivors are also helping themselves. In one of the relocation sites in Lushan's Baosheng Township, over 100 people are handing each other dishes, sharing the food they cooked with meat and vegetables they risked their lives to fetch from their damaged houses.

"My food is also theirs," one of them told Xinhua.

As of Sunday afternoon, water had been drained off from five reservoirs in Lushan, which suffered cracks and leakage and had posed a threat to people living in the lower reaches, to ensure the local residents' safety, according to a Lushan County government statement.

The quake-stricken area is expected to receive rainfall in the following three days, according to the Sichuan Provincial Meteorological Observatory.

Life miracle

The institute warned that rescuers should be aware of the secondary disasters such as falling rocks and landslides triggered by continual aftershocks, which have already caused great difficulties for the rescuers.

On the road linking Lushan and Baoxing, where the traffic has been newly restored, rolling stones triggered by the aftershocks kept hitting the roof of the passing vehicles.

"It is like being hit by 'an intense shower'," said Sun Tiexiang, a Xinhua reporter who was travelling with the car of a local medical team.

Bao Yuhuai, a senior officer with an armed police rescue team in Lushan told Xinhua that aftershocks and the ensuing landslides are the biggest challenges in road clearing.

"Some sections we just cleared have been buried by falling stones after the aftershocks," he said.

But the nonstop rescue did pay off. According to the head office of China's armed police, 5,800 police staff have saved 103 people in quake hit areas.

More than 2,300 firemen who are engaged in rescue work have saved 96 people, according to China's Ministry of Public Security.

The total number of the people saved in the quake region, however, is not immediately known.

In the small hours on Sunday, a 12-year-old girl, pulled out of her collapsed house in Lushan by rescuers nearly two hours after the quake, came to herself from a nearly 14-hour coma thanks to a major chest operation in a military hospital in Chengdu, capital of Sichuan.

"It's definitely a difficult operation in such a situation," said Su Yonglin, the vice head of the hospital. "But it is a very successful one."