China boosts intelligence reach in South China Sea, report says

The construction drive highlights Beijing’s effort to reinforce outposts despite ongoing territorial disputes with other claimants

China has upgraded surveillance and electronic warfare systems across several occupied reefs in the disputed South China Sea as it seeks to strengthen its defenses and expand intelligence capabilities, a new report shows.

Satellite images reviewed by the Washington-based Asia Maritime Transparency Initiative reveal new radar sites, antenna fields and other hardened structures on outposts in the Spratly Islands. The report, published Tuesday, details the most extensive changes in the past two years at Mischief, Subi and Fiery Cross reefs, where China has added new antenna arrays and reinforced older installations.

“These upgrades underscore the fact that a major function of China’s bases is to provide unparalleled intelligence, surveillance and reconnaissance coverage of the South China Sea,” the report says. They serve to support coast guard and navy operations, while allowing Beijing “to contest the use of the electromagnetic spectrum by others in the event of a conflict.”

The construction drive highlights Beijing’s effort to reinforce outposts despite ongoing territorial disputes with other claimants. Philippine and Chinese vessels frequently face off near a contested shoal to the north, with some encounters turning violent.

For its part, Manila asked its treaty ally the US to deploy unarmed MQ-9A aircraft — a drone known as “Reaper” that can be used for surveillance and strikes —  to help enhance shared maritime awareness. The US Marine Corps Forces, Pacific, said last month that the temporary stationing of the aircraft reflects both countries’ commitment to strengthening collective maritime security.

Though the bulk of China’s recent upgrades focus on electromagnetic spectrum, “Beijing is also investing in support facilities for equipment with more kinetic potential,” the AMTI report said, referring to offensive weapons capabilities.

Earth-fortified emplacements built along the western and northern edges of Mischief Reef over the course of 2023 often sit empty, but “the positions are likely capable of accommodating a wide variety of road-mobile weapons platforms, including artillery guns or rockets.”

The expansion comes as Vietnam accelerates its own island-building in the Spratly Islands, with reports in August showing work at eight reefs that previously weren’t part of its land-reclamation push that began in 2021. AMTI has previously estimated that Vietnam has created about 70% as much artificial land as China and is on track to surpass Beijing’s total.

“As Vietnam installs infrastructure on its own newly expanded outposts, it will be worth watching whether it also follows in China’s footsteps,” AMTI said in its report, “though Hanoi may find it easier to match the scale of Beijing’s dredging” than its electronic intelligence and surveillance footprint.