A Myanmar official told reporters that dozens of people were killed in areas close to the epicenter, where more than 240 buildings had collapsed.
"The death toll has increased to more than 60 now from those areas including Tarlay, Mine Lin and Tachileik townships," the official said.
He added that about 90 others were injured, and there were an undetermined number of people affected who had yet to be reached.
The 6.8 magnitude quake struck at 8:25 p.m. local time at a depth of only six miles, according to the U.S. Geological Survey.
Shaking was felt in several countries across Southeast Asia. Authorities in Thailand’s Mae Sai district, the country’s northernmost area on the border with Myanmar, report a 52-year-old woman was killed when a wall of her house collapsed during the quake.
Residents in Vietnam’s capital of Hanoi, two countries away from the epicenter, said the quake felt like a smooth rocking motion for several seconds.
One Australian living in a 27th-floor apartment in the Thai capital told the Associated Press that the shaking was terrifying.
Max Jones said the building swayed so hard he had to grab the walls to keep from falling.
Thailand's meteorological department said there had been dozens of strong aftershocks during the hours following the initial jolt.