At least 60 people have been killed and 90 others injured by a 7.0-magnitude quake in Myanmar's northeastern Shan state, authorities said Friday.
The quake, with an epicenter only 10 km deep and in Myanmar's hills, struck at 8:29 p.m. local time (1359 GMT) Thursday along Myanmar's borders with Thailand and Laos.
A 5.4-magnitude aftershock hit the area two hours later.
Over 240 houses collapsed in northeastern Myanmar.
The quake affected many areas in the region, and was felt strongly in the border town of Tachilek and slightly in Taunggyi, Bago, Shwegyin, Nay Pyi Taw, Mandalay and Toungoo.
Tachilek authorities advised people to stay out of their houses, but the situation was normal overall with no power blackouts and water supply disruption despite the damage to buildings.
The local Red Cross started its relief operation there Friday morning.
"Of real concern though are the more rural areas. There will be more, I am afraid to say, unhappy information coming throughout the day," Chris Herink, Myanmar country director for the charity World Vision, said. "It is a hilly area near the border between Thailand and Laos, the so-called Golden Triangle. There is a lot of commerce that goes on in the area."
In Yangon, only people living in high-rise buildings slightly felt the quake, and some people left their apartment buildings for safety reasons.
The quake also affected a wide swath of land in Thailand, Vietnam and China.
A 55-year-old woman was killed by collapsing walls in north Thailand's Chiang Rai city.
The quake was felt in the Thai capital Bangkok, a city some 772 km away from the epicenter, with buildings there shaking and swaying.
In Hanoi, buildings shook when the quake happened, causing panic among residents of apartment blocks. Residents in tall buildings felt dizzy and heard the shattering of windows.
Residents in south China's Yunnan Province and Guangxi Zhuang Autonomous Region also felt tremors.
The epicenter is 40 km from the Myanmar-China border.
In Nanning City, capital of Guangxi, many residents evacuated from buildings after they felt the tremors.
The epicenter was monitored at 20.8 degrees north latitude and 99.8 degrees east longitude, the China Earthquake Network Center said.