Two powerful aftershocks shook eastern Afghanistan in a span of 12 hours, the German Research Center for Geosciences (GFZ) said, triggering fears of more deaths and destruction on Friday in a region where about 2,200 people died in quakes in four days.
They follow two earthquakes that have already ravaged the South Asian nation, crushed by war, poverty and shrinking aid. The Taliban administration estimated 2,205 deaths and 3,640 injuries by Thursday.
A Reuters witness said continuous aftershocks hit the province of Nangarhar and details of the damage were still being collected.
Friday's earthquake of magnitude 5.4 struck the southeast at a depth of 10 km (6.2 miles), GFZ said, hours after one late on Thursday night.
The week's first earthquake of magnitude 6, just minutes before midnight on Sunday, was one of Afghanistan's deadliest, unleashing damage and destruction in the provinces of Nangarhar and Kunar when it struck at a shallow depth of 10 km (6 miles).
A second quake of magnitude 5.5 on Tuesday caused panic and interrupted rescue efforts as it sent rocks sliding down mountains and cut off roads to villages in remote areas.
With houses built mostly of dry masonry, stone, and timber, some families preferred to stay in the open rather than return home, as a precaution against aftershocks.
Naqibullah Rahimi, a spokesperson for the health department in Nangarhar province, said the epicentre of Thursday's earthquake was in the district of Shiwa near the border with Pakistan, and there were some initial reports of damage.
The earlier quakes flattened villages in both provinces, destroying more than 6,700 homes, and rescue workers pulled bodies from the rubble on Thursday.
Survivors in the earthquake-prone region are scrambling for basic amenities as the United Nations and other agencies warn of a critical need for funds, food, medical supplies and shelter, with the World Health Organization seeking funds of $4 million.
The earthquakes mainly happen in the Hindu Kush mountain range, where the Indian and Eurasian tectonic plates meet.

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