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Four people were killed, three were wounded, a government official said

The attack took place in Pakistan's Bajaur Agency

Islamabad, Pakistan CNN —  

Four people were killed and three others were wounded Wednesday in a blast caused by a remote-controlled explosive device in tribal Pakistan, a government official said.

The explosion struck a car of civilians traveling along a dirt road in the Mamund area in Bajaur Agency, according to Jamil Khan, an agency official.

Bajaur is one of seven semi-autonomous tribal districts in northwest Pakistan.