The administrative head of Zurmat district, Mohammad Zahir, was shot dead while on his way to office.
Paktia police chief Aghia Gul Sulaimankhel confirmed that in an exchange of fire with Zahir one of the attackers had been killed and one injured. The wounded attacker was arrested by police.
An increase of violence in the south and eastern Afghanistan has been reported in the recent months.
The area of Zurmat was a traditional stronghold of Hezb-i-Islami group headed by Gulbuddin Hekmatyar, a former mujahideen commander and former prime minister during the mujahideen government.