It said the quake was very shallow at a depth of 10 km (6.3 miles). It struck 55 km (34 miles) west of Dalbandin at 1:23 a.m. local time on Wednesday (2023 GMT on Tuesday).
High intensity jolts were felt in Karachi, Islamabad, Multan, Lahore, Quetta and many other parts of Pakistan. There was no immediate report of damage.
The Pacific Tsunami Center said the onshore quake had not triggered a tsunami in the Indian Ocean.
A major quake of this magnitude is capable of causing widespread and heavy damage and could pose fresh strains on a country still reeling from devastating floods last year which left more than 10 million people homeless.
On Oct. 8, 2005, a 7.6 magnitude quake 95 km (60 miles) northeast of the Pakistani capital Islamabad killed over 70,000 people.
More: Pakistan Flood: HAARP Used in Pakistan? – Urgent