At least three people were killed and four others injured on Monday in an explosion in northwestern Pakistan, police said.

The blast, which was carried out through an improvised explosive device, occurred in a market in Wana, the capital of South Waziristan, a tribal district near the border with Afghanistan.

District police chief Mohammad Tahir told reporters that the explosion targeted the vehicle of the head of the Ahmedzai tribe, who was among the deceased.

Ahmedzai tribe makes up over 60 percent of the local population.

No group has yet claimed responsibility for the attack.

The volatile South Waziristan was the founding headquarters of the Tehreek-e-Taliban Pakistan, an umbrella of several militant groups in Pakistan.

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