Myanmar's military government put the tentative death toll at 1,644 from the 7.7-magnitude quake that rocked the impoverished Southeast Asian nation.

Myanmar, also known as Burma, is in the throes of a prolonged and bloody civil war, which is already responsible for a massive humanitarian crisis.

Rescue operations are underway in the major stricken cities of Mandalay, the country’s No. 2 city, and Naypyitaw, the capital.

Scores of people are missing in the ruins of a high-rise building that was felled by the quake in Myanmar. Signs of life raised hopes on Saturday, but there was no update on survivors.

A powerful earthquake killed more than 140 people in Myanmar on Friday, authorities said, toppling buildings and wrecking infrastructure across a wide area, including a skyscraper under construction in neighbouring Thailand.

Emergency aid has streamed into Southeast Asia in the two days since a massive earthquake struck Myanmar and Thailand

It makes movement around the country both difficult and dangerous, complicating relief efforts and raising fears that the death toll could still rise precipitously. Read More: That Rocked Myanmar and Thailand The earthquake struck midday Friday with an epicenter not far from Mandalay,

In the hours after a massive earthquake flattened buildings in Myanmar's Mandalay on Friday, survivors scrambled through the debris using their bare hands in desperate attempts to save those still trapped.

In a censored nation that runs on rumor and omens, people in Myanmar wonder whether the latest disaster might be a portent of regime change.