A bomb exploded at an election office of an independent candidate in southwest Pakistan on Wednesday, the day before parliamentary elections are to be held, killing at least 14 people and wounding more than two dozen others, officials said.

The attack happened in Pashin, a district in Baluchistan province, said Jan Achakzai, the spokesperson for the provincial government. He said the wounded are being transported to a nearby hospital, and police said some of them were listed in critical condition.

No one immediately claimed responsibility for the attack, which came a day before Pakistan holds parliamentary elections.

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The bombing came despite the deployment of tens of thousands of police and paramilitary forces across Pakistan to ensure peace following a recent surge in militant attacks in the country, especially in Baluchistan.

The gas-rich Baluchistan province at the border of Afghanistan and Iran has been the scene of a low-level insurgency by Baluch nationalists for more than two decades. Baluch nationalists initially wanted a share of the provincial resources, but later they initiated an insurgency for independence.

Pakistani Taliban and other militant groups also have a strong presence in the province.