At least 20 people were killed and more than 300 injured when a magnitude 5.9 earthquake struck Pakistan’s southwestern Balochistan province early on Thursday.

The National Seismic Monitoring Center (NSMC) said the earthquake was centered near Harnai district and had a depth of 15 kilometers (9.32 miles).

The NSMC reported that the quake occurred at around 3.20 a.m. local time (Wednesday 2220GMT) and was also felt in the cities of Quetta, Sibbi, Pishin, and Chaman.

According to local media reports, 20 people, six of them children, were killed and more than 300 injured.

Many homes were damaged, while landslides also occurred in some areas.

"Still, many people are under the debris as dozens of houses collapsed in the area," the deputy commissioner of Balochistan province told Anadolu Agency.

Security forces, troops, and rescue workers have reached the earthquake-hit areas to conduct rescue and relief efforts, added Suhail Anwar Hashmi.

Meanwhile, the army has also deployed teams of doctors and paramedics to assist the civil administration for necessary medical care.

In a statement, the media wing of the military said that nine critically injured people had been airlifted to the provincial capital Quetta via army helicopters.

Authorities have reached Harnai for damage assessment and response, while a search and rescue team is being flown in from the city of Rawalpindi to help reinforce local teams, it added.