By Shirin Bhandari | 2025-10-15

The Philippines is facing mounting concerns over increasing incursions by Chinese underwater drones in its waters, a development that raises serious alarms about the nation's security and sovereignty.

In late September, a routine fishing trip off the coast of Linapacan, Palawan province, unexpectedly turned into a national security matter when local fishermen retrieved an object 12 feet (3.7 meters) long bearing Chinese markings.

The object showed signs of prolonged saltwater exposure and was later identified by the Philippine Coast Guard (PCG) as an underwater drone. The discovery underscores the escalating threat of unauthorized foreign activities in Philippine waters.

"It is mounted on a rugged metal frame, typical of components in autonomous underwater vehicles commonly known as underwater drones," said PCG spokesperson Commodore Jay Tarriela.

The device, frequently used to measure salinity, temperature and ocean depth, plays a crucial role in underwater surveillance and seafloor mapping.

Though these activities are common in marine research, deploying such technology without the host nation's consent violates international maritime law.

The discovery points to potential illegal surveillance and data gathering activities by foreign powers.

"Recovered units have shown capabilities for autonomous data processing, storage, and satellite transmission, with one case revealing encrypted communications to mainland China during operations," the PCG stated in a release.

1 suspicious drone after another

This underwater drone recovery is part of a broader pattern of similar findings made by the PCG since 2022. At least five underwater vehicles have turned up in various regions in the Philippines. Previous items include high-end communication modules, battery packs and logos linked to Chinese state enterprises.

The PCG has handed each of these devices over to the Philippine navy for forensic analysis. China may be deploying these drones as part of a broader surveillance and mapping campaign targeting Philippine maritime routes and critical data infrastructure, the pattern suggests.

Forensic analysis linked several earlier drones to Chinese defense contractors, confirmed Tarriela. Some units were found to to have China Telecom subscriber identity module cards, encrypted communication systems and satellite transceivers, with connections to Beijing-based firms.

The PCG commended the quick action of local fishermen for reporting the drone. It remains "vigilant in safeguarding our maritime domain and protecting the livelihoods of our fisherfolk," said PCG Commandant Adm. Ronnie Gil Gavan.

"This incident highlights the need for continued community awareness and a whole-of-nation approach to deter unauthorized activities in our waters," Gavan added.

A crucial region

The alarming frequency of these drone finds comes amid rising tensions between China and the Philippines, particularly in the South China Sea, where the countries have overlapping territorial claims.

The region, crucial for international shipping, holds valuable oil and gas reserves as well. Analysts consider the drones part of China's broader expansionist strategy in the South China Sea.

Earlier this year, Philippine intelligence agencies uncovered Chinese surveillance activities at military facilities across the country. They arrested Chinese nationals suspected of gathering sensitive information on US warship arrivals at the Subic Bay naval base.

Rocio Gatdula, a US-based defense economist and editor-in-chief of Georgetown Security Studies Review, suggested what China may be seeking in those waters.

"China's objectives may include mapping the Philippines' underwater topography to support submarine and naval operations, gathering intelligence for military, navigational and resource purposes, and reinforcing territorial claims through surveillance and presence," she said in an interview with USNI News.

The recent drone seizure underscores China's potential to compromise the situational awareness of the Armed Forces of the Philippines and to pave the way for future maritime incursions.

"Investing in technical support for analysis of recovered drones would support Manila's ability to counter incursions, improve early warning systems, and reinforce deterrence against persistent Chinese maritime aggressions," Gatdula added.