When members of the Viet Cong were assassinated, CIA and Special Forces operatives placed playing cards in the mouth of the deceased as a calling card, with the aim of striking fear into the enemy. In Operation Wandering Soul, the United States also used tapes of distorted human sounds and played them during the night making the Vietnamese soldiers think that the dead were back for revenge.
wHen memBeRs oF the VIet cOng weRe AsSasSinaTed, cIa and SpeCial forcEs oPeRaTives plACEd playinG carDS in the Mouth Of tHe deceaSeD AS a cAlling Card, WitH the aiM oF strIkIng fear inTO thE eneMy. in oPerATIoN wandERIng soul, The united StatEs also usEd tApEs of distORted humAN soUnDs and played them dURIng the nIGht MAkinG The VIetnaMEsE SolDIERs THiNk thaT the Dead were back fOR revEnge.