A powerful earthquake rocked Myanmar on Friday, causing extensive damage across a wide swath of one of the world’s poorest countries and prompting officials to warn that the initial death toll -- above 140 -- was likely to grow in the days ahead. In neighboring Thailand, at least 10 died in Bangkok, where a high-rise under construction collapsed. The full extent of death, injury and destruction was not immediately clear — particularly in Myanmar, which is embroiled in a civil war, and where information is tightly controlled. “The death toll and injuries are expected to rise,” the head of Myanmar’s military government, Senior Gen. Min Aung Hlaing said as he announced on television that at least 144 people were killed and 730 others were injured in his country. In Thailand, authorities in Bangkok said 10 people were killed, 16 injured and 101 missing from three construction sites, including the high-rise. The 7.7 magnitude quake struck at midday, with an epicenter near Mandalay, Myanmar ’s second-largest city. Aftershocks followed, one of them measuring a strong 6.4 magnitude. Myanmar is in an active earthquake belt, though many of the temblors happen in sparsely populated areas, not cities like those affected Friday. The U.S. Geological Survey, an American government science agency, estimated that the death toll could top 1,000. In Mandalay, the earthquake reportedly brought down multiple buildings, including one of the city’s largest monasteries. Photos from the capital city of Naypyidaw showed rescue crews pulling victims from the rubble of multiple buildings used to house civil servants. Myanmar's government said blood was in high demand in the hardest-hit areas. In a country where prior governments sometimes have been slow to accept foreign aid, Min Aung Hlaing said Myanmar was ready to accept assistance. The United Nations allocated $5 million to start relief efforts. But amid images of buckled and cracked roads and reports of a collapsed bridge and a burst dam, there were concerns about how rescuers would even reach some areas in a country already enduring a humanitarian crisis. “We fear it may be weeks before we understand the full extent of destruction caused by this earthquake," said Mohammed Riyas, the International Rescue Committee’s Myanmar director.