A magnitude 6.3 earthquake hit western Afghanistan on Saturday morning, the United States Geological Survey said, with the epicentre close to the region’s largest city.

The USGS said the epicentre was 40 kilometres northwest of the city of Herat, and was quickly followed by three aftershocks of magnitude 5.5, 4.7 and 6.2.

An AFP journalist in the city said residents and shopkeepers fled buildings when the first quake hit at about 11:00am, but that there were not yet reports of casualties or structural damage.

‘People are worried and terrified. Women, men and children, everyone is out of their homes,’ he said. ‘There have been aftershocks. Everyone is scared and tense. No one wants to stay inside.’

Hundreds of fatalities were possible, according to a USGS preliminary report.

‘Significant casualties are likely and the disaster is potentially widespread. Past events with this alert level have required a regional or national level response,’ it said.

USGS had earlier reported the shallow quake’s magnitude as 6.2.

Herat — 120 kilometres east of the border with Iran — is considered the cultural capital of Afghanistan.

It is the capital of Herat province which is home to an estimated population of 1.9 million, according to 2019 World Bank data.

In June last year, more than 1,000 people were killed and tens of thousands made homeless after a 5.9-magnitude quake — the deadliest in Afghanistan in nearly a quarter of a century — struck the impoverished province of Paktika.

In March of this year, 13 people were killed in Afghanistan and Pakistan by a magnitude 6.5 quake, which hit near Jurm in northeastern Afghanistan.

The country is frequently hit by earthquakes, especially in the Hindu Kush mountain range, which lies near the junction of the Eurasian and Indian tectonic plates.

Afghanistan is already in the grip of a grinding humanitarian crisis, with the widespread withdrawal of foreign aid since the Taliban returned to power in 2021.