The quake struck near the remote, mountainous city of Harnai in Balochistan province at about 3 a.m. local time, according to the US Geological Survey (USGS).
The USGS initially measured the quake at 5.7 magnitude, but revised it to 5.9 a few hours later. It also revised the depth from 20.8 kilometers (12.9 miles) to 9 kilometers (5.6 miles).
Some houses have collapsed in Harnai following the quake, according to the Balochistan Levies Force, the paramilitary law enforcement group in the province.
Sohail Afridi, the district commissioner of Harnai, confirmed the children’s deaths amid ongoing rescue efforts.
“Since 3 a.m. the rescue operation has been underway. The injured have been taken to the hospital via helicopter,” Afridi said, adding the situation is “currently under control.”
Harnai is located in a rural area and not easily accessible, welfare organization Edhi Foundation told CNN.
A road leading to Harnai has been blocked by a landslide, according to the Balochistan Levies Force. A video posted by the paramilitary group on Twitter showed officers working to clear the road, removing debris by hand in the headlights of two vehicles.
The last time a major earthquake hit Balochistan was in September 2013. A 7.7-magnitude quake struck the remote, sparsely populated area of Awaran, killing at least 330 people and injuring 445 others.