(CNN)The death toll from a strong earthquake that struck northeast Afghanistan on Tuesday could rise much higher, authorities warned Wednesday, after tremors were felt in several major Pakistani cities and as far away as the Indian capital New Delhi.
At least 13 people have been confirmed dead so far after the 6.5-magnitude quake sent residents fleeing from their homes in towns across northern Afghanistan and Pakistan, as it damaged buildings and triggered landslides.
The epicenter registered 40 kilometers (24 miles) southeast of the Afghan town of Jurm in the Hindu Kush mountain range at 187.6 kilometers (116 miles) deep, the United States Geological Survey reported.
In Afghanistan, at least four people were killed and 70 others injured in affected areas across the country, according to Sharafat Zaman Amar, spokesman for the Ministry of Public Health.
But the number of fatalities may climb as search and rescue teams reach more affected villages, said Shafiullah Rahimi, a spokesperson for the Ministry of Disaster Management. Some of the districts hit by the quake are extremely remote and don't have cell phone service, Rahimi added.
In Pakistan, at least nine people died -- including two children -- as houses and other buildings collapsed in the Khyber Pakhtunkhwa province, according to the Provincial Disaster Management Authority (PDMA). At least 44 others were injured in the province.
Noor Wali, a driver in Khyber Pakhtunkhwa's Lower Dir said he was eating at a restaurant when the tremors started.
"One wall of the restaurant fell in, we ran to save our lives. People were screaming," he said. "I was close to the mountain, felt like the whole mountain would slide into us, people were calling out for Allah."
Images from Saidu Sharif, a town in Pakistan's Swat Valley, show ambulances bringing quake victims to hospital as crowds gathered outside.
Ensuing landslides also blocked roads in the northern Pakistani city of Abbotabad, according to Bilal Faizi, spokesperson for the Khyber Pakhtunkhwa provincial rescue services.