Pakistan [Balochistan], May 21 (ANI): A devastating blast targeted a school bus in Pakistan's southwest Balochistan province, killing at least six people, including four children, and injuring 38 others, Al Jazeera reported, citing an official statement.

Yasir Iqbal Dashti, a government official in Khuzdar, said the attack occurred in the Khuzdar district, where the bus was picking up students for the Army Public School.

Balochistan Chief Minister Sarfraz Bugti said that the explosion was caused by a vehicle-borne Improvised Explosive Device (IED). The bus driver and his assistant were among the victims, while 46 students were on the bus. Authorities have airlifted critically injured children to Quetta for medical treatment, as per Al Jazeera.

'We have been air-lifting the critically injured children to Quetta from Khuzdar,' Bugti said.

Further, he said it was 'premature to confirm the nature of the attack' and that further investigations were ongoing. There was no claim of responsibility for the attack.

Prime Minister Shehbaz Sharif offered his 'sympathies' to the families of those who were killed by the 'brutality.'

Authorities said the death toll could increase due to the severity of the explosion.

Notably, in December 2014, the armed group Tehreek-e-Taliban Pakistan (TTP) hit the Army Public School in Peshawar, in Khyber Pakhtunkhwa province, killing more than 140 children.

Balochistan province, which is rich in minerals and natural resources, has been home to a decades-long conflict between the government and ethnic Baloch separatists, who demand secession from Pakistan.

Wednesday's attack came days after a car bombing killed four people near a market in Qillah Abdullah, also in Balochistan.

The BLA has a history of violent attacks, including a deadly assault on a train in March that killed 33 people, mostly soldiers. Earlier this week, the group promised more attacks on the Pakistani army and its collaborators, stating its goal is to 'lay the foundation for a peaceful, prosperous and independent Balochistan.' (ANI)