A blinding, toxic white shroud descended upon the residential rooftops of Yohmor on March 3, 2026, signaling the arrival of a weapon that has long haunted the hills of South Lebanon. As artillery-fired white phosphorus munitions burst in the air, scattering incendiary felt wedges over homes and farmland, the incident underscored a brutal, recurring reality of the ongoing border conflict. For residents of this village, the smoke was not merely a tactical maneuver—it was the precursor to fires that consumed private property and threatened the very foundation of their agricultural livelihoods.

This latest documented use of white phosphorus, verified by independent human rights monitoring, highlights the dangerous ambiguity of international law regarding incendiary weapons. As civilian displacement in South Lebanon hits critical levels, the deployment of this controversial substance—notorious for its ability to burn through flesh and bone while scorching the earth—poses an immediate danger to non-combatants. The incident in Yohmor stands as a stark reminder of the humanitarian and environmental toll exacted upon the region, where decades-old olive groves are being reduced to ash, and soil contamination threatens to stifle the local economy for years to come.

The Mechanics of a Controversial Weapon

The M825-series 155mm artillery projectile operates with chilling efficiency. Designed for smoke screening, signaling, and target marking, the munition functions by expelling felt wedges impregnated with white phosphorus upon detonation. These wedges ignite spontaneously when exposed to oxygen, creating a dense, suffocating cloud. However, the secondary effect of this chemical reaction is a persistent, intense incendiary fire that can reach temperatures exceeding 800 degrees Celsius.

• Ignition Temperature: Above 30 degrees Celsius.
• Reach: A single 155mm airburst can spread burning fragments over a radius of 100 meters.
• Persistence: The chemical can reignite even weeks after deployment if the residue is disturbed or exposed to oxygen.
• Environmental Impact: Severe soil contamination leading to long-term degradation and potential algal blooms in local water bodies.

Researchers, including experts from the American University of Beirut, have documented that the substance does not merely scorch surface vegetation. Its residues penetrate the soil, potentially poisoning the water table and rendering land barren. In a region where agriculture—particularly olive production—accounts for up to 80 percent of the local GDP in many border districts, the destruction is not just a tactical military outcome it is a systematic dismantling of civilian survival.

A Legal Gray Zone

The international community remains fractured over the regulation of white phosphorus. Protocol III of the Convention on Certain Conventional Weapons (CCW) is the primary instrument governing incendiary weapons, yet it contains significant loopholes that complicate accountability. While Protocol III prohibits the use of weapons primarily designed to cause burn injuries against civilians, it contains exceptions for multipurpose munitions, such as those used for smoke screening.

Because Israel is not a signatory to Protocol III, it maintains a unique position on the battlefield. Critics, including organizations like Human Rights Watch and Amnesty International, argue that the distinction between "smoke screening" and "incendiary attack" is rendered meaningless when the munition is deployed over densely populated residential areas. Legal scholars note that even if a weapon is not legally classified as an incendiary under specific treaty definitions, the principle of distinction in international humanitarian law—which requires combatants to separate civilian objects from military targets—remains absolute. When white phosphorus is fired into a village like Yohmor, the result is inherently indiscriminate, transforming the munition into a de facto incendiary weapon against civilians.

The Economic and Human Toll

For the farmers of South Lebanon, the conflict is measured in lost seasons and contaminated soil. Local agricultural councils estimate that thousands of olive trees, some of which are centuries old, have been destroyed since hostilities escalated in late 2023. Beyond the immediate destruction, there is the lingering fear of long-term toxicity. Farmers are grappling with the reality that their produce may face scrutiny in international markets, potentially rendering their hard-won harvests unsellable due to fears of chemical residues.

The financial impact is staggering. In previous assessments, lost agricultural land and damaged infrastructure have resulted in losses running into the billions of Kenyan Shillings (KES). For example, the destruction of a single hectare of productive olive grove represents a loss of potential revenue exceeding KES 6.5 million in projected long-term output. As families flee the border villages, many are leaving behind not just homes, but the generational wealth invested in the earth. The psychological trauma of having one's livelihood set aflame by a substance that cannot be easily extinguished only adds to the displacement crisis.

The Path Toward Accountability

International human rights bodies have consistently called for a suspension of arms transfers to parties that continue the use of white phosphorus in civilian-populated zones. They argue that without strict enforcement and independent, transparent investigations, the practice will continue to proliferate as a standard tool of asymmetric warfare. The incident in Yohmor is not an isolated tactical error it is part of a pattern of behavior that ignores the long-term consequences for human rights and regional food security.

As the international community debates the nuances of treaties and definitions, the reality on the ground remains brutal. The smoke from the Yohmor incident has cleared, but the fires it ignited continue to consume the agricultural heartland of South Lebanon. Until military actors are held to the rigorous standard of civilian protection, the white-hot legacy of these munitions will continue to define the landscape of the border conflict long after the artillery has fallen silent.