Updated

A major earthquake rocked Pakistan's southwest Saturday, sending people running into the street in panic just days after another quake in the same region killed 359 people, officials said.

The U.S. Geological Survey said on its website that a 6.8 magnitude quake was felt in Pakistan's southwestern Baluchistan province.

The Pakistani Meteorological Department measured the earthquake at 7.2 magnitude. The department said its epicenter was located about 90 miles west of the town of Khuzdar.

There were no immediate reports of casualties, said Abdur Rasheed, the deputy commissioner of Awaran district where both quakes were centered.

There may have been little left to damage after Tuesday's disaster. Few of the mud and homemade brick houses in the area survived the 7.7 magnitude quake that leveled houses and buried people in the rubble across the district of Awaran.

Since then tens of thousands of people have been sleeping under the open sky or tents. Rasheed said they had received reports that some homes damaged but still standing after Tuesday's quake had collapsed Saturday.

He said they are trying to get information whether people were living in some of the partially damaged homes.

"Today's earthquake damaged the already damaged buildings and homes," he said.

Chief Pakistani meteorologist Arif Mahmood told Pakistani television that it was an aftershock from this week's earthquake and such tremors might continue for weeks to come.

The aftershock struck about 18 miles to the south-southwest of where Tuesday's earthquake struck, the U.S. Geological Survey reported.