Manila: The National Security Council (NSC) on Monday said bottles recovered by the Philippine Navy (PN) from Chinese sampans operating near the BRP Sierra Madre (LS-57) in Ayungin Shoal in the West Philippine Sea (WPS) tested positive for cyanide.
According to Philippines News Agency, the Navy seized these bottles from Chinese sampans in February 2025 and on October 24, 2025. Laboratory analysis conducted by the National Bureau of Investigation (NBI)'s Forensic and Scientific Research Service has conclusively established that the yellow bottles seized from the sampans contain cyanide, a highly toxic chemical known to cause severe and irreversible damage to humans and marine ecosystems, NSC spokesperson Assistant Director General Cornelio Valencia Jr. said in a statement.
Valencia indicated that the deliberate use of cyanide raises serious concerns of illegal and destructive practices that threaten PN Navy personnel in BRP Sierra Madre, the fragile marine environment of the WPS, and the livelihood of Filipino fisherfolk. He emphasized that if such actions are proven intentional, they would constitute a blatant violation of Philippine environmental laws, international maritime norms, and the obligations of states under the United Nations Convention on the Law of the Sea (UNCLOS).
The use of cyanide in Ayungin Shoal is considered a form of sabotage aimed at killing local fish populations, depriving PN personnel of a vital food source, Valencia stated. Moreover, cyanide can damage the reef, potentially compromising LS-57's structural foundations. Severe damage to the reef not only threatens LS-57's stability but also allows Beijing to fabricate an environmental crisis, which it can then blame on the Philippines, he added.
Valencia highlighted that Ayungin Shoal lies well within the Philippines' exclusive economic zone, where the country exercises sovereign rights and jurisdiction. The operation of Chinese vessels engaging in activities involving hazardous substances in this area is deemed both irresponsible and unacceptable.
In response to this development, Valencia said the NSC has directed the Armed Forces of the Philippines, the Philippine Coast Guard, and all relevant agencies to heighten maritime domain awareness, strengthen patrols, and take all necessary measures to prevent further environmental harm and safeguard national security interests in the area. He reiterated that the Philippines will not tolerate any act-whether by state or non-state actors-that endangers its personnel or the marine environment, violates its sovereign rights, or undermines peace and stability in the WPS. The government remains resolute in defending the nation's territory, protecting its natural resources, and upholding the rule of law.
