More than 800 people have been killed - and nearly 3,000 injured - after a 6.0 magnitude earthquake struck eastern Afghanistan just before midnight on Sunday, the United Nations' humanitarian agency has said.

Most of the deaths occurred in Kunar province, officials say, warning that the death toll may rise significantly as entire villages have been destroyed.

The epicentre was in a remote mountainous area, making it difficult for rescue operations to be carried out. "The scale of devastation is unimaginable," a Taliban official said.

The disaster comes as Afghanistan reels from a severe drought, aid cuts and what the World Food Programme describes as an unprecedented hunger crisis.

The earthquake hit at 23:47 local time (19:47 GMT) on Sunday, some 27km (17 miles) east of Jalalabad - the country's fifth-largest city, in eastern Nangarhar province.

Faridullah Fazli was fast asleep at home in Asadabad, on the banks of the Kunar River, and the tremor jolted him awake.

"There was a very strong earthquake, accompanied by sounds that were very scary," he told the BBC.

"We didn't sleep until morning. After the earthquake, there were small tremors, and there are still."

Fazli said he went to the clinic in town, helping transport the dead and wounded into ambulances to be taken to a hospital further south in Nangarhar province.

"It was a very scary situation, just an atmosphere of fear and terror," Fazli said.

A resident of Mazar Dara, in the Nurgal region, said 95% of the village had been destroyed - with five to 10 injured people in every household.

The worst damage was in Kunar - a rugged, mountainous region with limited farmland.

Roads in the area are often mud tracks winding around mountains - while homes are made of clay, stones and mud.

The region has also seen massive flooding and landslides in the past few days, blocking access to many areas.

With roads blocked, rescue operations can only be carried out by air, and teams were unable to reach the area until the morning as helicopters could not land in the mountains at night.

However, more than 100 flights have since been conducted in clear weather since.

"Entire villages are flattened, roads to deep mountainous areas are still closed. So now, for us, the priority is not finding dead under the rubble, but rather reaching out to those injured," a Taliban official in Kunar province said.

"Most of the dead are under rubble. We are doing everything, but it doesn't seem possible soon," he said.

There are cases of people trapped under the rubble for hours and reportedly dying as they awaited rescuers.

Syed Raheem - one of those taking part in rescue efforts - said that even though many had been saved, there were fears others were still trapped.

"Some people sent us messages that there are houses that are destroyed, and some people are still under the rocks," he told the BBC.

Jalalabad's main hospital was already overwhelmed, being right at the centre of the crossing point for the tens of thousand Afghans being deported from bordering Pakistan.

On Monday, it was quite chaotic - with injured, helpless relatives looking for their loved ones, volunteers and rescue teams still running around the place.

An inconsolable woman said she had lost family members in the quake, while an old man appeared dazed and lost, unable to speak to anyone.

A doctor said around 460 victims had been brought in since the earthquake - 250 admitted, the others treated and discharged.

Internet connectivity in those areas is very limited, making communication and co-ordination difficult.

Since August 2021, Afghanistan has been under the control of the Taliban, whose government is only recognised by Russia.

Several aid agencies and non-governmental organisations suspended their work in Afghanistan when the hardline Islamist group swept back into power.

Most foreign donations to Afghanistan have been suspended and international sanctions, which date back to when the Taliban were first in power in the 1990s, are still in place - although exemptions have been made for humanitarian relief.

The Taliban government has launched an appeal for aid following Sunday's earthquake.

Afghanistan is no stranger to earthquakes as it sits on a number of fault lines.

In 2023, a series of quakes in the Herat province killed more than 1,000 people, a year after a similar number were killed in Paktika province.

The latest earthquake was so deadly because it was so shallow - striking at a depth of 8km (5 miles) - and was felt 140km away in the capital, Kabul, as well as in neighbouring Pakistan. To be classed as a shallow, an earthquake must occur less than 70km below the surface.

Shallow earthquakes are common in Afghanistan, particularly in the foothills of the Himalayas where tectonic plates are sliding past each other.(BBC)

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