The death toll from a huge earthquake that hit Myanmar and Thailand passed 1,000 on Saturday, as rescuers dug through the rubble of collapsed buildings in a desperate search for survivors.

The shallow 7.7 magnitude quake struck northwest of the city of Sagaing in central Myanmar in the early afternoon, followed minutes later by a 6.7 magnitude aftershock.

The quake destroyed buildings, downed bridges, and buckled roads across swathes of Myanmar, with massive destruction seen in Mandalay, the country's second biggest city and home to more than 1.7 million people.