A group of about 30 Afghan National Army personnel intruded into the Kurram tribal region and attacked a check post in Dalasa area yesterday morning.
Two Pakistani personnel were injured in the incident, military officials told the media.
The attack by the Afghan troops was repulsed with heavy artillery fire, the officials said.
On July 12, Afghan troops reportedly intruded into a village in Kurram Agency and killed two civilians in an exchange of fire with local residents.
Islamabad and Kabul have traded angry charges over a string of cross-border attacks reportedly carried out by Pakistani Taliban fighters based in Afghanistan.
Afghan officials have said the Pakistan Army fired hundreds of rockets across the border.