HARNAI: An earthquake of magnitude 5.9 struck parts of Balochistan early on Thursday morning, killing at least 20 people and injuring over 300 others, the Provincial Disaster Management Authority (PDMA) said.

According to the National Seismic Monitoring Centre, the earthquake was centred near the province's Harnai district and had a depth of 15 kilometres.

It added the quake had a longitude of 67.96 east and a latitude of 30.08 north.

Tremors were felt in Quetta, Sibbi, Pishin, Muslim Bagh, Ziarat, Qila Abdullah, Sanjavi, Zhob and Chaman, the PDMA said in its initial report.

It further said the "exact damage" has not yet been confirmed.

The death toll was also confirmed by Deputy Commissioner of Harnai District Sohail Anwar Hashmi. He said six children were also among the deceased.

The injured, which include women and children, have been shifted to the District Headquarters Hospital in Harnai, he said.

Balochistan Chief Minister Jam Kamal Khan Alyani shared that assistance and evacuation efforts were under way.

"Blood, ambulances, emergency assistance, [helicopters] and rest all things are placed ... All departments are working on it," he tweeted.

PDMA Director General Naseer Ahmed Nasir said there had been some landsliding in mountainous areas. He added that houses within a 15km radius of Harnai had been destroyed and rescue teams were busy in relief efforts.

The official said that government buildings had been damaged as well.

Separately, Home Minister Mir Ziaullah Langove said five to six districts were affected on a "major scale" and data was still being collected.

He said the highest number of deaths and injuries had been reported in Harnai, adding that critical patients would be shifted to Quetta immediately.

"They are our people, the state's resources are for them. People won't be left helpless. Those who have suffered a loss will be compensated," the minister said.