
By Priam Nepomuceno | Philippine News Agency
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.
It said the Navy seized these bottles from Chinese sampans in February 2025 and on Oct. 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 said 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.
“Such actions, if proven intentional, 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),” he added.
Valencia said the use of cyanide in Ayungin Shoal is a form of sabotage that seeks to kill local fish populations, depriving PN personnel of a vital food source.
“Moreover, cyanide can damage the reef, which can ultimately compromise LS-57’s structural foundations. If the reef is severely damaged, it not only threatens LS-57’s stability, it also allows Beijing to fabricate an environmental crisis, which it can then blame on the Philippines. It has in the past accused LS-57 of polluting the shoal in an effort to distract from its own illegal activities,” he said.
Valencia further said Ayungin Shoal lies well within the Philippines’ exclusive economic zone, in which the country exercises sovereign rights and jurisdiction.
“The operation of Chinese vessels engaging in activities involving hazardous substances in this area is both irresponsible and unacceptable,” he added.
With 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.
“Let it be clear: 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,” he said. (PNA)
