The earthquake occurred at 8:02 am local time (0002 GMT) in Lushan county and the epicentre had a depth of 13 km (8 miles), state news agency Xinhua reported.
China's Twitter-like Sina Weibo micro-blogging service was abuzz with earthquake hitting the country. Users of Sina Weibo stated that quake was felt strongly by residents in neighbouring provinces and in the provincial capital city of Chengdu, causing many to rush outside.
The U.S. Geological Survey initially put the magnitude at 7, but later revised it down. The latest earthquake occurred close to where the massive temblor struck in 2008, killing almost 70,000.
Rescue operations at the quake-hit regions are on. The Chinese Red Cross had deployed relief teams with supplies of food, water, medicine and rescue equipment to the disaster areas.
The military surveyed the region by air as all roads were blocked for several hours after the quake. The officials also released aerial photos which were shown on television. The photos tell how the earthquake jolted the area.