A major earthquake measuring 7.8 on the Richter scale has hit Wenchuan County in southwest China's Sichuan province. 

A major earthquake measuring 7.6 Richter Scale jolted Wenchuan County of Southwest China's Sichuan province at 2:28 p.m. on Monday.(Xinhua Photo)

President Hu Jintao has ordered all-out efforts to rescue quake-hit victims. Premier Wen Jiabao was on his way to the hit area to direct the rescue work. Chengdu Military Area Command has dispatched troops to help with disaster relief work in the earthquake-stricken County.

The incident took place at 2:28 p.m. on Monday. The epicenter of Wenchuan County lies in the Tibetan-Qiang Autonomous Prefecture of Aba, about 100 kilometers northwest of the provincial capital Chengdu. Tremors were also reported in many other parts of China, including Ningxia, Qinghai, Gansu, Chongqing, Hunan, Hubei, Shanxi, Shaanxi and Shanghai, and as far away as Thailand and Vietnam. Cracks were seen on walls of some residential structures in downtown Chengdu, but no buildings collapsed.

A crevice is seen in a building in Chengdu, capital of southwest China's Sichuan Province, after an earthquake occurred on May 12, 2008. A major earthquake measuring 7.8 Richter Scale jolted Wenchuan County of Sichuan province at 2:28 p.m. on Monday. (Xinhua Photo)

The telecom networks in Chengdu and Chongqing were down after the quake. An underground water pipe was broken underneath a viaduct close to Chengdu's southern railway station, and a road was flooded.

Meanwhile, another earthquake measuring 3.9 on the Richter scale jolted Tongzhou District in east Beijing minutes later. The quake was also felt in neighboring Tianjin.

A street in Chengdu, capital of southwest China's Sichuan Province, is covered by water after a water pipe blew out during an earthquake on May 12, 2008. A major earthquake measuring 7.8 Richter Scale jolted Wenchuan County of Sichuan province at 2:28 p.m. on Monday. (Xinhua Photo)

(CCTV May 12, 2008)