Maybe there was a clash and the Afghan/ISAF troops called out for air support in 'self defence'.
See , I told you this is entirely possible.
The alleged clash for which air support was called for was between Afghan militants in Eastern Afghanistan (not in Pakistan) & the Afghan forces, not between Pakistani soldiers & Afghan soldiers.
I'm not going to keep repeating myself again. Please stop making up stories, & if you think there was a clash between Afghan soldiers & Pakistan Border Forces in this incident; or if any Afghan soldiers were found in Pakistan, or if any Afghan soldiers were injured or killed in this incident, please quote appropriate sources. Please don't make up fictional stories.