A STRONG earthquake hit a remote, mostly rural and mountainous area of southwestern China's Sichuan province early yesterday, killing at least 156 people and injuring about 5500 close to where a big quake killed almost 70,000 people in 2008.

The magnitude 6.6 earthquake, China's worst in three years, occurred at 8.02am local time in Lushan county near Ya'an city. The epicentre had a depth of 7.5 miles, the US Geological Survey said.

The quake was felt by residents in neighbouring provinces and in the provincial capital of Chengdu, causing many people to rush out of buildings, according to accounts on China's Twitter-like Sina Weibo microblogging service.

State media said 156 people had been confirmed dead, with more than 5500 injured.

President Xi Jinping and Premier Li Keqiang said all efforts must be put into rescuing victims to limit the death toll.

After arriving at the disaster zone by helicopter, Li directed earthquake relief efforts from a plaza in Longmen township in Lushan, state news agency Xinhua said. He asked that a road be opened to Baoxing county, one of the areas most affected by the earthquake, and that rescuers "act quickly" in their efforts, Xinhua quoted Li as saying.

"The current most urgent issue is grasping the first 24 hours since the quake's occurrence, the golden time for saving lives," Li said.

Xinhua said 6000 troops were heading to the area to help with rescue efforts. State television CCTV said only emergency vehicles were being allowed into Ya'an, though Chengdu airport had reopened.

Most of the deaths were concentrated in Lushan, where water and electricity were also cut off. Pictures on Chinese news websites showed toppled buildings and people in bloodied bandages being treated in tents outside the hospital, which appeared only lightly damaged.

Rescuers in Lushan had pulled 32 survivors out of rubble, Xinhua said. In villages closest to the epicentre, almost all low-rise houses and buildings had collapsed, according to footage broadcast on state television.

"We are very busy right now, there are about eight or nine injured people, the doctors are handling the cases," one doctor at a Ya'an hospital said.

The hospital was seeing people arrive with head and leg injuries, she added.

The China Meteorological Association warned of a possibility of landslides occurring in Lushan county this weekend, the agency said in a statement on its website.

A resident in Chengdu, 85 miles from Ya'an city, told Xinhua he was on the 13th floor of a building when he felt the quake. The building shook for about 20 seconds and he saw tiles fall from nearby buildings.

Ya'an is a city of 1.5 million people and is considered one of the birthplaces of Chinese tea culture. It is also the home to one of China's main centres for protecting the giant panda.

Sichuan is one of the four regions which are major producers of natural gas in China, and its output accounts for about 14% of the nation's total.

The US Geological Survey initially put the magnitude at 7, but later revised it down. The devastating May 2008 quake was 7.9 magnitude.

■china