The Frontier Constabulary (FC) personnel on Wednesday detained an Afghan intelligence agent in Chaman town, near the Pak-Afghan border.
According to FC spokesperson, the Afghan officer was arrested during a raid in Shuhdan area.
Explosives and heavy weapons including four SMGs, hundreds of bullets and sniper scope were recovered from a house where the suspect was hiding, the spokesperson added.
Pak-Afghan border is penetrated by militants for terror activities in both countries. Its length allows easy passage for militants.
Both states have vowed on a number of occasions to curb these elements together.