At least 25 people died and 35 others were injured when a bomb exploded at a Sufi shrine in southern Pakistan's restive Balochistan province on Saturday, officials said.

The blast hit a crowd of worshippers participating in a ceremony at the shrine of Sufi saint Shah Noorani in Khuzdar district, some 760 kilometres (472 miles) south of provincial capital Quetta.

"At least 25 people have been killed in bomb blast at Shah Noorani shrine," Commissioner of Kalat region Mohammad Hashim told AFP.

Zulfiqar Hashmi, Deputy Commissioner of nearby Lasbela division confirmed the deaths and said that more than 35 people suffered injuries in the attack.