Secretly Mining the Enemy

This would have to be very top secret. It could be done in two different ways. Weapons could be produced with a built in explosive that detonate when the weapon is used that would kill the person that uses it and those that are in close approximately to it. There could be a detonating device that would operate by satellite remote control or by sensors that would indicate that people are near by. These bobby trapped weapons could be sold to weapon dealers that are known weapon suppliers to the enemy. They could be put in a location where they could be stolen by the enemy. There might be ways of getting an explosive into the enemy headquarters where it would explode severely burn those in that meeting. It could be a bobby trapped pen, book, camera, etc. It would have to be done in such away that it would be difficult to trace the source of the exploding item. The same thing could be done to larger equipment such as tanks, airplanes, etc. that would be sold to friends now but may turn into an enemy later. If they later become the enemy, a signal could be sent to make that item unfunctional or blow it up.