A powerful earthquake struck Herat Province in Afghanistan near the border with Iran early Wednesday, several days after two major quakes in the same area killed more than 800 people.

The magnitude 6.3 temblor struck northwestern Afghanistan at 5:22 a.m. local time at a depth of about 10 kilometers, according to the U.S. Geological Survey. The epicenter was just outside Herat City, the provincial capital and cultural hub.

The latest quake sent people in Herat City running out of their homes for the second time in five days. Thousands of others had already been sleeping outside in tents, or in makeshift shelters made of blankets and tarp, still terrified from the dual quakes that rocked the area on Saturday.

“When my body started shaking I realized it was another quake,” said Nadar, 52, who goes by one name. “Everyone sleeping outside was shouting and screaming.”

The Saturday quakes, both of which were also 6.3 magnitude, caused mud-brick homes in several districts to come crashing down. At least seven tremors followed the initial quakes.

This is a developing story. Check back for updates.

Andrés R. Martínez contributed reporting.