Mystery surrounds the discovery and confiscation of 100 kilos of depleted uranium, found stored in three separate cities across the country.

Two days after the news broke, neither the National Bureau of Investigation (NBI) nor the Philippine Nuclear Research Institute (PNRI) — the agencies responsible for handling such incidents — have issued any official updates.

Three individuals have been arrested, with two of them reportedly posting bail. The extent of potential contamination at the locations where the depleted uranium was found has yet to be determined. No announcement has been made on whether the communities where the materials were discovered are safe from contamination.

In a statement on its website, PNRI said it alerted the NBI to the group’s illegal trade in hazardous materials. An entrapment was set in Pasay City which led to the arrest of Mae Vergel Zagala and Arnel Gimpaya Santiago. During the raid, the NBI seized three kilograms of black powder which tested positive for Uranium-238 and Uranium-235.

Roy Cabeses Vistal, the suspected leader of the group, managed to evade capture initially but was later apprehended in Cagayan de Oro City.

A subsequent raid of Vistal’s residence at Mega Heights Subdivision on 28 October raised the possibility of American involvement in the operation after witnesses reported seeing five Americans in military uniforms.

The NBI said the group claimed it had sourced the uranium in Cebu. In a search in Mandaue City on 8-9 November, agents seized metal blocks weighing 60 kilograms which tested positive for Uranium-238 and Uranium-235.

Although the Philippines has some uranium deposits, particularly in Palawan and Mindanao, these are not mined on a commercial scale. The country has historically avoided mining uranium due to environmental concerns, safety issues and the potential for misuse in nuclear weapons production and other illicit activities. This has led to speculation that the depleted uranium may have been smuggled into the country.

Uranium-238 and Uranium-235 are critical for nuclear energy and weapons production and are tightly regulated due to their risks. U-238, while not directly usable in reactors and weapons, can be converted into Plutonium-239, a material used in both. Although weakly radioactive, U-238 has a long half-life, posing long-term environmental and health risks.

U-235, which makes up only 0.7 percent of natural uranium, is highly radioactive and fissile, essential for nuclear reactors and weapons. Enriched U-235 sustains a chain reaction, making it critical for energy production and weaponry. Its high radioactivity makes it especially dangerous if mishandled.

Improper handling of either can lead to contamination, radiation exposure and severe health effects, including cancer. The use of these materials is tightly controlled to prevent misuse in nuclear weapons development.

The lack of official information surrounding the discovery has led to widespread speculation. One theory suggests the uranium may be part of a larger hoard of “precious metal” that treasure hunters in Northern Mindanao mistook for platinum bars. These materials were reportedly sent for testing and monitored by the International Atomic Energy Agency, which likely prompted the PNRI to notify the NBI.