A spokesman for the provincial government said at least 12 people died Saturday, Dawn News reported.
In one village, 60 mud-walled houses collapsed, killing four people.
Rescue workers also found the bodies of four people killed in Wednesday's quake while going through the rubble looking for new victims.
The U.S. Geological Survey said the epicenter of Saturday's earthquake was about 60 miles northeast of the Awaran district, the area most badly hit Wednesday.
Local officials put the combined total deaths for the two quakes at 371.
The earthquake shook the provincial capital, Quetta. The provincial assembly was in session at the time and television coverage of the session showed members hurriedly leaving the chamber.
Earthquakes in the 6.0 to 6.9 range are considered strong and can do severe damage to poorly constructed buildings.
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