China rushed Wednesday to reach victims of a strong earthquake that jolted its mountainous southwest, killing at least 13 people and rattling a region where memories of a colossal 2008 seismic disaster remain fresh.
The 6.5-magnitude earthquake struck Sichuan province late on Tuesday, tearing cracks in highways, loosing rockslides, damaging structures and sending panicked residents and tourists fleeing into the open.
Thousands of people, including many visitors to a popular national park near the epicentre, remained outside overnight, according to reports, and were being evacuated to safety Wednesday as nerves were kept on edge by more than 1,000 aftershocks that rippled across the region.
No reports of serious damage or large-scale casualties had emerged by Wednesday afternoon but aid organisations warned that it will take time before a clear picture comes into focus due to the area's difficult geography.
The quake killed at least 13 people and injured 175, 28 seriously, the local government of Aba prefecture said.
Images from the quake zone showed cars and buses tossed into ravines or crushed by giant boulders apparently jolted loose from surrounding hills, while uniformed paramilitary police with shovels were pictured digging through rubble for victims.
Elsewhere, injured victims were photographed being treated in hospitals while stunned crowds, fearing more tremors, waited out in the open to be evacuated, particularly near the epicentre at Jiuzhaigou.
- 'We just ran' -
Official Xinhua news agency said at least five deaths occurred in Jiuzhaigou, a picturesque national park and UNESCO World Heritage Site famed for its karst rock formations, waterfalls and lakes.
It said more than 34,000 people were visiting the popular tourist area at the time of the quake and that 31,500 tourists had been moved to safety.
"Nearly all the tourists are being evacuated," a local tour company worker, who gave only her surname Yan, told AFP by phone.
"We slept overnight in tour buses and have been staying in the open ground. Landslides are pretty bad, rocks keep falling down."
China's official earthquake monitoring agency said more than 1,000 aftershocks had been detected, the most powerful reaching magnitude 4.8 on Wednesday.
China's National Commission for Disaster Reduction estimated as many as 100 people may have perished, based on census data in the sparsely populated region, and that tens of thousands of homes may have been damaged.
Another sparsely populated part of China was also rocked by a strong quake Wednesday morning.
A 6.3-magnitude tremor shook northwestern Xinjiang region, more than 2,000 kilometres (1,200 miles) from Sichuan, according to the USGS, followed by aftershocks of 5.2 and 5.3 magnitude.
At least three people were injured there when their home collapsed, Xinhua said.
- 'All-out efforts' -
President Xi Jinping called for "all-out efforts to rapidly organise relief work and rescue the injured" in the Sichuan quake, according to Xinhua.
Provincial fire authorities said at least 1,250 soldiers had been deployed to Jiuzhaigou, along with hundreds of vehicles, 30 sniffer dogs and 55 devices used to detect life underneath rubble.
The Sichuan quake struck at a shallow depth of 10 kilometres, the USGS said, and was reportedly felt hundreds of kilometres from the epicentre. Shallow quakes tend to cause more surface damage.
It evoked memories of a massive 8.0-magnitude earthquake that devastated wide areas of the same region in 2008, leaving 87,000 people dead or missing in China's worst seismic disaster in a generation.
"I was also in Jiuzhaigou in 2008 during the last big quake, so I knew what it was. This felt even stronger," local restaurant owner Tang Sesheng told AFP by phone.
"People didn't dare grab anything like money or clothes -- we just all ran outside right away."
Several other people contacted by AFP reported seeing structures collapse, while others spoke from their cars amid a mass exodus on traffic-choked narrow mountain roads pelted by falling rocks.
The 2008 quake set off deadly landslides in the region, obliterating towns and damming rivers, creating menacing "quake lakes" that forced the evacuation of thousands downstream as the army worked to clear the blockages.
The People's Daily posted video footage on Twitter reportedly showing stranded tourists keeping warm around a campfire at night and photographs of people sleeping under blankets in the street.
The Red Cross Society of China said it was sending emergency specialists and volunteers to assist affected communities, while Save the Children was also mobilising teams.
"Given the frequent landslides in the rainy season and potential massive secondary disaster following the big earthquake, Save the Children is deeply concerned about the safety of children and women in the affected areas," said the charity's operations director in China, Dr Zhang Hongxia.