Separatist Baloch fighters have in past claimed responsibility for attacks in the southwestern Balochistan province.

Nine bus passengers have been killed after gunmen kidnapped them in Pakistan’s restive southwestern Balochistan province, officials have said.

The passengers were taken from several buses on Thursday evening, the provincial government spokesman, Shahid Rind, said on Friday.

The bus was travelling from Balochistan to the central region of Punjab. It is thought the travellers were targeted due to their Punjabi ethnicity, officials said.

The bodies of the victims, riddled with bullet wounds, were found in the mountains overnight, another government official, Naveed Alam, said.

Prime Minister Shehbaz Sharif and Interior Minister Mohsin Naqvi confirmed the incident and strongly condemned the killings. “The blood of innocent people will be avenged. The killing of innocent citizens is an open act of terrorism by India-sponsored terrorists,” Sharif said.

There was no immediate reaction from India to his statement. No one has yet claimed responsibility for the attack.

The Balochistan Liberation Army (BLA), separatist Baloch fighters, have in the past been involved in such incidents, killing passengers after identifying them as coming from the eastern Punjab province.

The BLA is the strongest of a number of groups involved in a rebellion, who have for years operated in the area bordering Afghanistan and Iran, a mineral-rich region.

The ethnic Baloch fighters blame the authorities in Pakistan for stealing their regional resources to fund spending in Punjab province.