At least three policemen were killed and 16 others injured when a roadside bomb exploded in Pakistan’s southwestern Balochistan province on Tuesday, officials said.

The attack occurred near Kund Masuri in Mastung district, where a police bus carrying personnel from a training center in Kalat district was targeted by an Improvised Explosive Device (IED), according to Shahid Rind, spokesperson for the Balochistan government.

“The condition of two injured is critical,” Rind said, adding that all the injured have been moved to nearby hospitals, while seriously wounded officers were being transferred to Quetta for advanced treatment.

The personnel belonged to the Balochistan Constabulary and had been deployed for security at a sit-in protest organized by the Balochistan National Party-Mengal (BNP-M), Xinhua reported.

Following the explosion, emergency protocols were activated at Bolan Medical College Hospital and Civil Hospital Quetta to ensure rapid medical response.

Authorities have launched an investigation and requested a detailed report on the incident. No group has claimed responsibility for the attack yet.

Balochistan Chief Minister Sarfraz Bugti condemned the bombing and directed health officials to provide top-tier medical care. He also instructed provincial Health Minister Bakht Muhammad Kakar to personally oversee the treatment process.

“There will be zero tolerance for any negligence in treating the injured,” Bugti stated. “Those responsible for this heinous act will not be spared under any circumstances.”

Balochistan, the largest yet least populated province in Pakistan, has been the scene of frequent violence, often targeting security forces and attributed to separatist and extremist groups.