The UN's humanitarian agency says preliminary reports indicate at least 800 have died across four provinces in Afghanistan following the 6.0-magnitude quake.
United Nations Office for the Coordination of Humanitarian Affairs (Ocha) says at least 2,000 people are estimated to be injured, many of them in remote and mountainous areas cut off from access to rescue crews, BBC reports.
At least 12,000 people are believed to be directly impacted by the earthquake, including from damaged buildings or infrastructure Ocha says.
The quake, at a shallow depth of 8km (6 miles), shook buildings from Kabul to Pakistan's capital Islamabad.
The remote area where it struck makes providing accurate estimates hard, as officials warn of high casualty figures.
Dozens of houses are "under rubble", sources from the Taliban government say, while officials report entire villages being destroyed.
A 6.0 magnitude earthquake struck Afghanistan's mountainous eastern region at 23:47 local time on Sunday (20:17 BST).
Its epicentre was 17 miles (27km) away from Jalalabad, the country's fifth-largest city in Afghanistan’s eastern Nangarhar province.
The earthquake has also affected the Kunar and Laghman provinces, and was felt 140km (87 miles) away in the country's capital Kabul.
It will take a while before the extent of the earthquake's damage is fully known.
This is mountainous terrain. These areas are extremely challenging to reach even in the best of times, which is really hampering rescue and relief operations.
We've been told that the road leading to the epicentre has been blocked because of a landslide, so the Taliban government is using helicopters to get people out.
With the region being difficult to access, any kind of rescue operations are going to be slow-moving.