Five people have been killed and 55 injured in the Afghanistan province of Nangahar, the head of the provincial hospital in the region has said.
Charities working in northern Afghanistan/Pakistan say it may be difficult to assess earthquake damage in the region because of a lack of communication links to the affected areas.
ABC News' South Asia Correspondent James Bennett has tweeted:
Charities working in nthn Afghanistan/Pakistan say little comms to region, so difficult to assess impact of 7.5mag quake 250km NNE Kabul
India's prime minister Narendra Modi has said the country "stands ready" to provide assistance where required following a powerful earthquake that was felt in India, Afghanistan and Pakistan.
Heard about strong earthquake in Afghanistan-Pakistan region whose tremors have been felt in parts of India. I pray for everyone's safety.
I have asked for an urgent assessment and we stand ready for assistance where required, including Afghanistan & Pakistan.
A woman in Pakistan has described the earthquake felt across the region as the "most horrible three minutes of my life".
The most horrible 3 minutes of my life. Have never come across something like this before. Never. Allah Reham!!! #Earthquake
At least four people have killed in the powerful 7.5 magnitude quake.
The powerful quake felt across Afghanistan, Pakistan and India was "biggest and longest earthquake I have ever experienced", according to one eyewitness.
NBC News producer Fazul Rahim, who is based in Kabul, said in a tweet: "That was by far the biggest and longest earthquake I have ever experienced. Hope it has not caused any damage and casualties!"
At least four people have been killed and scores injured in north-western Pakistan after a magnitude 7.5 earthquake struck the region, according to officials.
The US Geological Survey has downgraded the quake felt across Afghanistan, Pakistan and India from 7.7 to 7.5.
Hospitals in the northern Afghanistan provinces of Panjshir, Parwan and Baghlan are "on standby" following a powerful earthquake in the region.
Afghanistan journalist Bilal Sarwary tweets that the health ministry is checking with medics in the regions and that all hospitals have been told to be on standby.
A powerful earthquake first hit a remote area of northern Afghanistan - not Pakistan as initially reported.
The tremor was also felt in India and Pakistan.
The quake was 196 km (120 miles) deep and centred 82 km (51 miles) southeast of Feyzabad in a remote area of Afghanistan in the Hindu Kush mountain range.
There have no immediate reports of damage or injuries.
An earthquake has shaken buildings in the Afghan capital Kabul, according to Reuters.
Earlier, the US Geological Survey said that a magnitude 7.7 quake struck in northern Pakistan.
A powerful 7.7-magnitude earthquake has struck near northern Pakistan, the US Geological Survey said.