Over 400 survivors of a powerful earthquake that struck Myanmar last Friday have been extracted from under rubble in the Mandalay region.

Mandalay, Myanmar's second-largest city and home to more than 1.7 million people, suffered some of the worst destruction, with many residential buildings collapsed into piles of rubble.

Local and international rescue teams have been working round the clock to scour the ruins even as the critical 72-hour window has passed. As of Monday, 403 people had been rescued and 259 bodies had been recovered in Mandalay, local authorities said.

The magnitude-7.9 quake has claimed 2,719 lives, with 4,521 people injured and 441 still missing in the country, according to official figures released on Tuesday. At least 19 people died in neighboring Thailand as a result of the earthquake.

The toll is expected to rise as rescuers reach towns and villages where communications have been cut off by the quake.

For many, the danger has not yet dissipated. Hundreds of residents spent a fourth night sleeping in the open, either because their homes were destroyed or because they were afraid that aftershocks would cause more damage.

Fear of aftershocks has also forced Mandalay's 1,000-bed general hospital to move its patients into the car park, where they lie on gurneys with only a thin tarpaulin rigged overhead to shield them from the fierce tropical sun.

"Having lived through the terror of the earthquake, people now fear aftershocks and are sleeping outside on roads or in open fields," an International Rescue Committee (IRC) worker in Mandalay told Reuters.

"However, in towns and cities, safe spaces are scarce. There is an urgent need for tents, as even those whose homes remain intact are too afraid to sleep indoors."

The IRC said its teams found people also urgently needed medical care, drinking water and food.

The Myanmar government has asked the population to pause at 12:51:02 on Tuesday, precisely four days after the country was hit by the quake, and said media should halt broadcasting and display mourning symbols, while prayers will be offered at temples and pagodas. It declared a week-long mourning period the previous day.

(With input from agencies)