North-east Burma has been rocked by two 7.0 magnitude earthquakes, close to the borders with Laos and Thailand, the US Geological Survey has reported.
They struck seconds apart at 1355 GMT and were centred about 70 miles (110 km) from the northern Thai city of Chiang Rai, the agency said.
The first quake was shallow, at a depth of 6.2 miles (10km), while the second was much deeper at 142.5 miles (230km).
Tremors could be felt as far away as Bangkok and Hanoi.
The area where the quakes struck is sparsely populated and remote.
The BBC's Rachel Harvey in Bangkok said it could be a while before the extent of the damage is known.
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