And they also tried a method of blasting ghost sounds in planes which is the precursor to

The Huk rebels- Hukbalahap, were a people’s army against the Japanese occupation of the Philippines in WW2. They were strongly communist. After the country was secured and the US military occupied it, the Huk rebels were attempting to take over and form a communist government. The USA did not like this. EG Landsdale was sent to head a CIA backed US government program in the Philippines to gain influence/control over the islands to forward US global interests. Landsdale and team conducted numerous covert and psychological operations. Landsdale had his team study local mythology and they conducted operations such as using curses and omens and iconography of local legend to undermine the people’s support of the Huk army and weaken morale and resolve. One such operation included using a myth similar to “vampires” of a blood sucking occult entity living in the wilds. More or less as Jessie says they made it seem like Vampires were attacking Huk rebels in the hills to spread fear and stigma