Below is an excerpt from a book that shows an example of how a myth may be used to propagate a psychological operation (psyop).

One [Lansdale-initiated] psywar operation played on the superstitious dread in the Philippine countryside of the asuang, a mythical vampire. A psywar squad entered an area, and planted rumors that an asuang lived on where the Communists were based. Two nights later, after giving the rumors time to circulate among Huk sympathizers, the psywar squad laid an ambush for the rebels. When a Huk patrol passed, the ambushers snatched the last man, punctured his neck vampire-fashion with two holes, hung his body until the blood drained out, and put the corpse back on the trail. As superstitious as any other Filipinos, the insurgents fled from the region.

Source:
Victor Marchetti and John D. Marks, The CIA and the Cult of Intelligence: (New York, N.Y.: Dell Publishing Co., Inc., 1974), 50-51.