KHOST, Afghanistan, July 10 (Xinhua) -- Unknown armed men opened fire on a civilian vehicle in Paktia province east of Afghanistan killing 13 commuters on Saturday, spokesman for provincial administration Rohullah Samoon said.

"The bloody incident took place in Chamkani district at 11:00 a. m. local time as a result 13 innocent civilians including two Afghans and 11 Pakistanis were martyred," Samoon told Xinhua.

Three more civilians were injured in the bloody attack.

Without giving more details, the officials said that the ill- fated Pakistanis were going home when the fatal incident occurred.

However, he could not identify the attackers, adding that the investigation is underway.

On the same day Saturday, Taliban militants carried out a suicide car bomb attack against NATO-led troops in Ismael Khil district of the neighboring Khost province.