Philippines raises security concerns over Chinese-linked underwater drones

By AFP and Global Watch | 2025-04-23

Amid escalating Chinese territorial disputes with the Philippines in the South China Sea, the recent discovery of suspected Chinese underwater drones has raised serious security concerns.

Five underwater drones found by Filipino fishermen were capable of gathering information that could aid in "underwater warfare," the country's military said April 15, noting at least one had relayed a signal to China.

The revelation follows months of confrontations between the Philippines and China in the South China Sea and comes as Manila prepares for large-scale military exercises with treaty ally the United States this month.

The five underwater drones were found between 2022 and 2024 in locations deemed "important strategically" for the defense and security of the country and for international maritime navigation, Philippine military officials reported April 15.

"They have the capability to receive, to process, to store and to transmit data through satellite communications to a station on land, to a mothership, or to other drones," said Rear Adm. Roy Trinidad, the Philippine navy's spokesperson for South China Sea issues, according to the Philippine News Agency.

Their data collection served purposes "beyond navigation," Trinidad said, adding that the devices were used to map underwater terrain and collect bathymetric data, crucial for undersea military strategy.

Chinese origin

Philippine officials confirmed that one of the five recovered drones -- a yellow "HY-119" model retrieved off Masbate Island on December 30 -- was of Chinese origin.

"It is a Chinese-made submersible drone," Philippine National Police Maritime Group chief Jonathan Cabal said during a January 15 Senate hearing, according to Philstar.com.

"There is no such submersible drone in our commercial enterprises. That's why we surmised that this is not commercially available, but of a military grade or for scientific purpose."

Brig. Gen. Andre Dizon, police commander of Masbate, pointed out the drone's satellite communication capabilities for transmitting and receiving data and voice messages, Naval News reported January 3.

"Based on the markings found, this was a Chinese underwater navigation and communication system," Dizon said.

A Naval News report in January indicated the drone is a "Sea Wing" glider developed by the Chinese Institute of Oceanology, capable of reaching a significant depth of more than 6.4km and potentially augmenting China's submarine fleet with submarine detection and tracking abilities.

Though Philippine authorities have not officially named China as the source of the other drones, the evidence points strongly in that direction.

One of the drones had a subscriber identity module card that had last communicated with a mainland Chinese network, while others bore Chinese markings.

Assessments by Philippine officials give a 55% to 80% likelihood that the drones were deployed by China, based on components and communication links.

Trinidad also reported the discovery of an iridium transceiver with a serial number from HWA Create. With its headquarters in Beijing, HWA Create focuses on defense, civil, government and industrial solutions.

Meanwhile, another drone was found to have conductivity, temperature and depth (CTD) sensors and a battery pack marked "China Electronics Technology Group (CETG)."

The CETG Corporation is a state-owned enterprise for civil-military integration of information technology. CTD sensors can provide crucial data for understanding the ocean's physical properties.

Strategic placement

The recovery locations of the drones, spanning from Luzon in the north to Mindanao in the south, including two near the Balintang Channel south of Taiwan and others off the north coast of Luzon, underscore their strategic placement across key maritime channels and critical chokepoints like Masbate Island and Mindanao.

This broad geographic distribution reinforces Philippine officials' concerns of a long-term covert surveillance effort targeting Philippine waters.

The Chinese embassy did not immediately respond to requests for comment.

Department of Energy Undersecretary Alexander Lopez, spokesperson of the National Maritime Council, warned that such underwater activity may reflect efforts to assert control over contested areas.

"Basically, that is how far they would like to venture into our maritime territory," he said in April, according to news reports.

While data like bathymetric readings can be used for scientific purposes, Trinidad emphasized their central role in submarine operations, sonar evasion and seabed warfare -- an especially vulnerable domain for a maritime nation like the Philippines.

"This is a national security concern," said Senate Majority Leader Francis Tolentino in April. He urged public vigilance. China uses these drones to collect underwater data for military purposes, he said, as reported by the Philippine News Agency.

Tolentino stressed the importance of protecting the Philippines' sovereign rights in the West Philippine Sea through diplomatic and legal channels.