A strong aftershock jolted south-west China on Sunday killing at least one person and injuring 400 others, state media said, nearly a fortnight after an earthquake killed tens of thousands in the same area.
More than 70,000 houses toppled during Sunday's tremor in Sichuan province, state television reported. The 5.8 magnitude aftershock was epicentred 40 km (25 miles) west-north-west of Guangyuan, the US Geological Survey said.
A local official in Guangyuan county said one person was killed and 24 hurt in collapsed houses or landslides, Xinhua state news agency reported. As the aftershock occurred, hundreds of troops carrying explosives were trekking through the area, attempting to reach a "quake lake" that threatened a secondary disaster.
Concerned by a steep rise in the water level of a giant lake at Tangjiashan, authorities want to blast a hole in the barrier before it bursts and causes a flash flood. Thousands have been evacuated from below the lake as a precaution.
"I can assure (that) the people who need to be moved have already been safely relocated," said a general, who gave his name only as Zhou, watching over hundreds of troops outside the wrecked town of Beichuan as they readied to march to the lake.
Premier Wen Jiabao, who believes the overall death toll from quake earlier this month could exceed 80,000, has said the main concerns are secondary disasters like flooding and landslides, epidemics, and providing shelter for the 5 million displaced. Hundreds of aftershocks have rattled the area since the 7.9 magnitude quake on May 12.