A car bomb exploded near a market in Pakistan’s restive southwest, killing four people and wounding 20 others, a government official said Monday, as violence intensifies in the region.

Axar.az reports, citing ABC news, the attack occurred Sunday night in Qillah Abdullah, a city in Balochistan province bordering Afghanistan, said Deputy Commissioner Abdullah Riaz.

The blast also damaged several shops and the outer wall of a nearby building housing paramilitary forces, he said. No group immediately claimed responsibility for the bombing.

However, suspicion is likely to fall on ethnic Baloch separatists, who frequently target security forces and civilians in Balochistan and other parts of the country.

Shahid Rind, a spokesperson for the Balochistan government, condemned the bombing and said an investigation is underway.