At least four people were killed and 32 others injured in an explosion in Pakistan's southwestern Balochistan province on Saturday, local media and officials said.

The incident happened in Turbat district of the province, where a convoy was attacked and a bus in it was struck during the assault, officials told Xinhua on condition of anonymity.

A senior police officer and his family members were injured in the attack and shifted to a nearby hospital, local reports said.

The banned Balochistan Liberation Army claimed the attack in a post on social media, while the Pakistani authorities have not confirmed the attack.