When people think about war, they often picture weapons, soldiers, and battlefields. But not all conflicts are fought with physical force. Some conflicts are fought by shaping thoughts and emotions, using fear, uncertainty or sound to disturb and influence people.
Between August and mid-October 2025, residents of Ou Beichoan Commune in Cambodia reported hearing disturbing sounds at night, including ghostly cries and engine noises coming from the nearby Thai border. These sounds often lasted for hours and caused distress among villagers, particularly children and the elderly. Cambodian authorities later accused Thai military units of broadcasting these sounds intentionally as a form of psychological intimidation. The Cambodian Human Rights Committee (CHRC) called the incident a “violation of border peace” and urged the United Nations to investigate.
The CHRC stated in a letter to UN, “On 10 October 2025, the CHRC received credible reports from local authorities and affected civilians…indicating that units of the Royal Thai Armed Forces broadcast haunting sounds resembling wailing ghosts through large loudspeakers from 10:44 PM until 12:04 AM; followed by continuous aircraft engine noises played from 3:22 AM to 3:53 AM, deliberately directed toward Cambodian villagers in nearby communities with the apparent intent to disturb and terrorize. These sounds, described as intense, high-pitched noises lasting for prolonged periods, have disrupted sleep, provoked anxiety, and caused physical discomfort among residents, including women, children, the elderly, the sick and persons with disabilities.” (Fresh News Asia). Cambodia’s Senate President Hun Sen warned that the noise could raise tensions. He said Cambodia does not want to criticize any ally and called for the ceasefire to be respected. (The Cambodia Daily)
Thailand has not officially denied the incident involving the ghostly sounds near the Cambodian border. Instead, Interior Minister Anutin Charnvirakul appeared to defend the broadcasts, suggesting they were intended to support Thai soldiers stationed near the border. He reportedly praised the individual responsible for playing the sounds, stating that it helped keep troops alert and asserting, “It’s my land, my home.” (Thai Newsroom)
This response indicates that Thai authorities view the broadcasts as a domestic matter rather than an act of aggression, despite Cambodia’s concerns and calls for international investigation.
Though unusual at first, the “ghost sound” dispute reflects a broader pattern in Asia, where sound has been used as a tool in psychological warfare. One of the earliest and most well-known examples comes from the Vietnam War, when the U.S. military launched Operation Wandering Soul, a campaign designed to unsettle enemy troops by playing eerie audio recordings at night. These recordings included whispers, cries, and voices made to sound like fallen Viet Cong soldiers, along with Buddhist funeral music and haunting messages urging fighters to abandon their posts and return home. The tactic was based on Buddhist belief that souls of the dead wander in suffering if not properly buried in their homeland. By exploiting these cultural fears, the U.S. aimed to lower morale and encourage desertion among enemy forces.
One of the most well-known recordings, called Ghost Tape Number Ten, included chilling lines such as, “My body is gone. I am dead, my family. Tragic, how tragic! My friends, I come back to let you know that I am dead. I am dead. I am in hell. … Friends, while you are still alive … go home! … Go home, my friends—before it is too late.” (Foreign Policy)
Although the overall success of the operation was mixed, it remains one of the earliest examples of modern psychological warfare using sound. Even when Viet Cong soldiers realized the sounds were recordings, their reactions, such as firing toward the speakers often revealed their positions, which was strategically useful for U.S. forces.
While Operation Wandering Soul is one of the earliest known examples of using sound in psychological warfare, similar tactics have appeared in other parts of Asia. In more recent years, sound has continued to play a role in border tensions, especially in regions where military standoffs are common, and psychological pressure is used to influence behavior.
Along the Line of Control (LoC) between India and Pakistan, loudspeakers have long been used during periods of tension. In some cases, Pakistani troops have broadcast evacuation messages to Indian border villages ahead of shelling, which caused confusion and fear among civilians. (Times of India)
In Indian villages like Tillawari, mosque loudspeakers have been used to warn residents during cross-border firing. These alerts help coordinate movement to safer areas and have become part of local response systems. A soldier stationed near the LoC pointed to a Pakistani bunker flying a flag and said, “There are snipers sitting there watching us; since they are on a higher altitude it makes our side more vulnerable.” He had asked everyone, including local officials, to leave the village, noting that his own bunker had been fired at earlier that morning. (Newslaundry)
Over time, the use of loudspeakers has become a regular part of life in many border communities. These broadcasts serve practical purposes, such as issuing warnings or coordinating movement, but they also reflect the ongoing tension between the two sides. Even periods of silence can signal changes in activity or intent along the border. One of the most visible and long-running examples of psychological broadcasting happens on the Korean Peninsula, where both North and South Korea have used loudspeakers as tools of persuasion and pressure for more than half a century.
Since the 1960s, each side has installed high-powered speaker systems along the Demilitarized Zone (DMZ), one of the world’s most fortified borders to project propaganda, news, and music deep into enemy territory. The goal is not only to inform but to influence morale and loyalty among border troops.
In 2024, psychological warfare on the Korean Peninsula took a high-tech turn. South Korean activists began launching GPS-guided “smart balloons” into North Korea, carrying leaflets, Bibles, radios, and even parachute-deployed speakers that broadcast anti-regime messages and North Korean songs. These devices, designed to fly deep into North Korean territory, were part of a renewed campaign to challenge the North Korean regime’s control over information. Simultaneously, South Korea resumed loudspeaker broadcasts across the Demilitarized Zone (DMZ) for the first time since 2018, playing K-pop music and democratic slogans. These actions were met with fierce retaliation from North Korea, which launched over 1,000 balloons filled with garbage and animal waste into South Korea. A week later, another report noted that South Korea’s broadcasts could be heard up to 20 kilometers inside North Korea, raising debate over their effectiveness and the potential to escalate tensions. (Reuters)
The then South Korean President Park Geun-hye stated that the broadcasts would continue until North Korea issued a formal apology for the landmine incident. She said, “We need a clear apology and measures to prevent recurrence of these provocations and tense situations. Otherwise, this government will take appropriate steps and continue loudspeaker broadcasts.” (BBC News)
For analysts, the DMZ remains a powerful example of how sound is used not just for communication, but as a strategic tool to influence morale and assert control. In this context, information becomes a weapon, and the ability to shape perception is seen as a form of power.
From Cambodia to Korea, these examples reveal how modern conflict extends beyond weapons. Psychological operations are designed to influence emotions, perceptions, and decisions, whether through ghost sounds, music, or rumors. These effects are small, but they still affect people in real ways.
Verification Note: This report is based on publicly available news reports and official statements as of October 2025. Sources considered unreliable, exaggerated, or unverified were not included.
Afiya Ibnath Ayshi is a Security and Strategic Reporting Fellow at Bangladesh Defence Journal. She covers defence, foreign affairs, and humanitarian issues, focusing on how regional and global developments influence Bangladesh’s security and diplomacy. A graduate in English from the University of Dhaka, she brings a research-based and balanced approach to her work.