Actually, I think that (putting on my tin foil hat) that there are more sophisticated ways of getting innocents to murder on behalf of government agencies. Hypnotism, drugs, and outright assassination seems to be employed.
There is a movie called "Telefon" with Charles Bronson a number of years back. Moles are activated by a telephone message to commit mass murder. Unfortunately, it may not be far from the truth. I also have seen videos of the weapon that induces heart attacks in its victims. You can see the testimony before Congress with the weapon itself on Youtube.
Link?