CHENGDU, China - Heavy rain and a chemical fire hampered urgent recovery efforts Thursday in an earthquake-shattered area threatened by a rising lake.
State television reported that a stockpile of bleach used to disinfect quake ruins ignited in a storage building in the town of Leigu, in devastated Beichuan county. Several of the troops spraying the building were gasping for air and being treated by medics.
The official Xinhua News Agency reported that more than 800 people were evacuated to avoid a cloud of dense chlorine gas caused by the blaze.
As in many destroyed towns, officials have been spraying bleach on streets and rubble in an effort to prevent disease breakouts. Thousands of people are still missing and their bodies could be buried in the rubble. Rats and other scavengers have been reported in some places.
"The soldiers have inhaled the fumes. It has affected their bodies and they are in the military hospital now," said a soldier identified by CCTV as the leader of the fire crew. His name was not given. He said 61 soldiers were injured. Xinhua reported that four people were injured. It was not immediately possible to reconcile the different injury tolls.
It was not immediately clear why the bleach ignited, though substances in it can turn explosive if heated or mixed with hydrocarbons such as those in diesel fuel.
The rain grounded helicopters and hampered work to drain a lake formed when a landslide triggered by the magnitude 7.9 earthquake blocked a river. The lake, dubbed Tangjiashan, has been rising by several yards a day.
Beichuan has been sealed off by troops and officials say it will be rebuilt somewhere new.
Some 158,000 people downstream from the new lake have been evacuated, and officials have pledged to warn other nearby residents in case of flooding so they have time to flee, the official Xinhua news agency reported.
Of 34 lakes created by the earthquake, 28 are at risk of bursting, Xinhua said.
With roads to the area cut off, helicopters have airlifted heavy equipment to dig drainage channels. Heavy rain prevented aircraft from flying, CCTV reported, but workers were continuing efforts to clear debris despite the weather. The rain was a minor addition to the rising water compared to the river feeding the lake.
In the past three days of around-the-clock work, troops have dug a channel 50 yards wide and 300 yards long, CCTV said.
The government raised the confirmed death toll from the quake to 68,516, with 19,350 people still missing. The increase of about 400 deaths was the smallest since the Cabinet started announcing a toll.
The government has already said it expects the final toll to surpass 80,000.
The military also released some details of the massive recovery effort. Lu Dengming, commander for the area around the provincial capital of Chengdu, said more than 2,500 miles of damaged roads have been repaired and 70 million cubic feet of ruins cleared, the official Xinhua New Agency reported.
Some 178,000 troops, militia and reservists were taking part in the operation, and had delivered more than 510,000 tons of relief materials by land and air, including tents and prefabricated houses and schools, Lu said.
China, which is struggling to house the millions left homeless, said it was in talks with Tokyo about the sensitive issue of using the Japanese military to deliver earthquake relief aid, in what would be the first significant military dispatch involving the two countries since World War II.
Beijing has allowed rescue and medical experts from several countries to help in the relief operation -- a switch from China's usual approach of preferring to handle internal matters on its own.
"Given the magnitude of this disaster, if some countries or militaries are ready to provide us with material in urgent need, we will express our welcome," Foreign Ministry spokesman Qin Gang said, adding that Japan's offer would be further discussed by the countries' defense departments.
Japan invaded China and conquered large parts of it in the 1930s before being defeated by the Allies in 1945. Many Chinese still strongly resent Japan for its military aggression at that time.
South Korean President Lee Myung-bak, who is visiting China, will travel to the disaster region Friday, Qin said.
Also Thursday, the head of the world's most famous panda reserve, badly damaged by the earthquake, said it was looking for a new home.
"What I'm worrying about are secondary disasters, such as severe aftershocks," Zhang Hemin, chief of the Wolong Giant Panda Reserve, said by phone. "The road is easily blocked by rocks falling from the mountain. There would be no way to get the food in."
The reserve is just 20 miles from the epicenter of the quake. Five reserve staff members died.
One panda remains missing. Conditions remain so bad that the government last week arranged an emergency food shipment of about 5 tons of bamboo for the 47 pandas still at the reserve. Many panda enclosures were heavily damaged.
Some pandas have been moved to another breeding center in Chengdu, and eight were flown to Beijing last weekend for a previously scheduled stay at for the Olympics.
The government has put business losses from the disaster at $9.5 billion, with estimates of total damage to factories, roads and ther infrastructure running as high $86 billion.
