Deadly quake spells disaster for 'isolated' Afghanistan.

KABUL -- A deadly 6.1 magnitude earthquake that struck Afghanistan in the early hours of Wednesday morning has killed around a thousand people and left at least 600 injured, disaster management officials said.

Said to be the worst quake in Afghanistan since 2002, the seismic event occurred 44km from Khost, near the border with Pakistan, according to the US Geological Survey (USGS).

The tremors from the quake were felt by about 119 million people in Pakistan, Afghanistan and India, the European-Mediterranean Seismological Centre (EMSC) said on Twitter.

Read more: Earthquake kills 30 Pakistani tribesmen in North Waziristan

The EMSC put the earthquake's magnitude at 6.1, though the USGS said it was 5.9.

Interior ministry official Salahuddin Ayubi said the death toll was likely to rise 'as some of the villages are in remote areas in the mountains and it will take some time to collect details.'

However, images and videos coming out of the country showed houses reduced to rubble and bodies swathed in blankets lying on the ground.

An unknown number of people remained stuck under rubble and in outlying areas, health and aid workers said, while rescue operations were complicated by difficult conditions including heavy rains, landslides and many villages being nestled in inaccessible hillside areas.

'Many people are still buried under the soil. Rescue teams have arrived and with the help of locals are trying to take out the dead and injured,' a health worker at a hospital in the hard-hit Paktika province said.

Disaster experts and humanitarian workers said the impoverished hilly areas struck by the quake were especially vulnerable, with landslides and poorly built houses adding to widespread destruction.

Eyewitness accounts

'We were all sleeping at home... and the room fell over us,' said Gul Faraz as he received treatment for injuries with his wife and children at a hospital in Paktika. Some family members had been killed, he said.

'All the houses in our area were destroyed, not one, but the entire region has been destroyed.' Most of the confirmed deaths were in the eastern province of Paktika, where 255 people were killed and more than 200 injured, Ayubi said. In the province of Khost, 25 were dead and 90 had been taken to hospital.

Adding to the challenge for Afghan authorities is recent flooding in many regions, which has blocked stretches of highway.

Hospitals in rural Afghanistan have come under pressure as well. From her hospital bed in...