More than 50 people have died in a magnitude-6.8 earthquake in Burma which struck near the Lao and Thai borders.
It struck at 1355 GMT on Thursday and was centred about 70 miles (110 km) from the northern Thai city of Chiang Rai, the US Geological Survey said.
It was felt 800km to the south in the Thai capital Bangkok, and in the Vietnamese capital, Hanoi.
The quake was shallow, at a depth of 6.2 miles (10km). There are fears the casualties could be much higher.
"The death toll of the quake has increased to more than 50 in Tarlay and Mine Lin townships," said one unnamed official quoted by AFP.
"Roads are also closed. According to the information that we have, more than 130 buildings collapsed because of the quake. There might be more casualties and damage."
"Total death toll has now reached nearly 50 and the number of the injured is about 40 while over 100 buildings were destroyed," a Civil Administration official in Tachilek on Burma's border told Reuters by telephone.
The BBC understands that the districts of Baan Thadeua and Baan Laen, within a 40km radius of Tachilek, have been worst hit.
Cracks are visible in roads and rice fields have been wrecked by rising silt and water.
On the Thai side of the border, paddy fields and temples from Chaengsaen to Mae Sai have been damaged.
A Burmese official told AFP news agency that 25 people had been killed in the town of Tarlay alone.
The official said five monasteries and 35 buildings in the town had collapsed and that roads in the area had been damaged, making access for rescue parties difficult.
One woman in Thailand's Chiang Rai province, close to the epicentre, was killed when a wall collapsed.
The BBC's Rachel Harvey in Bangkok said it could be a while before the extent of the damage is known.
Earlier reports suggested there had been two strong earthquakes moments apart in the same area, but the USGS later clarified that there had been just one quake.
Click to view image: 'Burma earthquake: More than 50 dead in tremor near'
|Liveleak on Facebook|