At least 400 people were killed and more than 2,000 injured or trapped in collapsed buildings in the strongest earthquake to hit Taiwan in nearly a century, officials said today in Taipei.
The magnitude of the quake has been variously estimated at between 7.3 on the Richter scale according to Taiwanese officials and 8.1 by the French National Earthquake Surveillance Network.
A magnitude of seven can cause widespread, heavy damage.
The temblor hit around 1.47 a.m. (1747 GMT yesterday) with its epicentre 12.5 km west of the scenic Sun Moon Lake, in central Taiwan's Nantou county, the Seismology Centre said.
In Washington, a spokesman for the US Geological Survey said the earthquake was recorded at a magnitude of 7.6 on the Richter scale.
The French surveillance network in Strasbourg, which measured the strength of the Taiwan quake at 8.1, suggested it was the same intensity as the 1906 earthquake that devastated San Francisco.
Each increase of one point in the Richter scale is equivalent to a tenfold increase in ground motion.
No force 9 earthquake has ever been recorded, but the 1976 earthquake that destroyed the Chinese city of Tangshan, killing more than 600,000 people, was recorded at 8.3 on the Richter scale.
"The quake was the largest one to hit western part of the island in nearly 100 years," said Mr Liu Yue-long, deputy director of the Seismology Centre.
Scenes of mayhem were evident in Taiwan and other cities, with several children being pulled from the rubble of buildings.
Dazed people shed tears eyeing the damage to their homes and milled about in the open as ambulances and fire engines screeched past.
Tremors were felt as far away as in Hong Kong where some residents woke up to notice their building shaking and lights dimming.
"There could be more aftershocks measuring up to 6.0 on the Richter scale in a week," warned Mr Kuo Kai-wen, director of the centre.
More than 200 aftershocks have been recorded by the seismologists since the 'quake.
An official of China's State Seismological Bureau said in Beijing that Xiamen and Wenzhou cities in southeastern China and Guangdong province in the south also felt the temblor. He said details of damage and casualties were awaited.
A 12-storey building in Taipei collapsed. "Ten-odd people were rescued from the rubble," the Taipei mayor Mr Ma Ying-jeou said. "The first four storeys of the building sank beneath the ground."
The quake originated one km under the earth's surface.
Witnesses in Taipei spoke of fresh aftershocks, power outages throughout the island, building collapses, objects falling off apartment blocks and people fleeing their homes.
State radio said more than six million households islandwide were hit by the power outage triggered by the collapse of a pylon in central Taiwan.
The Taichung mayor, Mr Liao Yunglai, said: "This is one of the strongest earthquakes I have felt in my life. Many buildings collapsed and there are damages to roads and other infrastructure.
"We have formed an emergency team to deal with it. I urge people to stay calm and stay in open areas."
The country's top leadership was reported to be meeting in an emergency session.
Official records show an earthquake measuring 7.1 on the Richter scale hit the southern county of Chiayi in 1906, killing 1,258 people and injuring 2,385 others and destroying some 12,000 houses.
Seismologists have warned southern Taiwan could be in for a potentially devastating quake following a relatively calm 30-year cycle.
A quake measuring 4.0 on the Richter scale hit the Lisbon area at 11.54 p.m. (21.54 GMT) yesterday without causing any casualties or serious damage, the civil protection service reported. The epicentre of the tremor was located 10 miles southwest of Cascais, a tourist town just west of Lisbon. The quake was felt in several parts of the capital.