The bombing in the province's Guzara district was carried out by two men who were riding a motorcycle, Khaama Press reported.
Guzara district chief Nisar Ahmad Popal said the bombers meant to assassinate him, but their explosives went off before they were able to enter the district government building.
There were no civilian or security force casualties, Popal said.
So far, no group has taken responsibility for the attack.
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