China’s military announced on Wednesday that it monitored and "drove away" a US destroyer that sailed near the disputed Scarborough Shoal, in what it described as an unauthorized intrusion into its waters. The incident marks the first known US military operation within the shoal’s vicinity in at least six years.

According to the Chinese Military's Southern Theatre Command, the US destroyer, the USS Higgins, entered waters near the shoal "without approval of the Chinese government." The statement accused Washington of "seriously violating China’s sovereignty and security" and pledged that Chinese forces would remain on "high alert at all times."

The US' Indo-Pacific Command declined to comment, according to Reuters, referring inquiries to the US Navy’s 7th Fleet, which did not immediately respond. The US embassy in Beijing also offered no immediate statement.

The Scarborough Shoal, located in the South China Sea, has long been a point of contention between China and the Philippines. The broader region is one of the world’s busiest waterways, with an estimated $3.4 - 5.3 trillion in global trade passing through each year. Roughly one-third of all global shipping transits these waters, and up to 90% of China’s energy imports move along these routes.

Additionally, the seabed is believed to hold between 11–17 billion barrels of oil and up to 266 trillion cubic feet of natural gas, in addition to rich fishing grounds that account for around 15% of global fisheries.

Chinese sovereignty claims

China’s claims in the South China Sea are based on what it describes as "historic rights" dating back over two millennia, outlined in the so-called nine-dash line. Chinese records cite early exploration by sailors during the Han Dynasty and later administrative control by successive dynasties. Beijing argues that it was the first to discover, name, and govern the islands and shoals in the region.

In 2016, an international arbitral tribunal ruled against the legal basis of these claims. China rejected the decision as “null and void” and has since continued to maintain its position on sovereignty.

The United States has regularly conducted "freedom of navigation" operations (FONOPs) in the South China Sea since 2015 in an attempt to give the image of control in the area, sailing warships within 12 nautical miles of Chinese-controlled features. In 2024 alone, US forces carried out hundreds of aerial reconnaissance missions, deployed multiple carrier strike groups, and operated nuclear submarines in the region.

Nonetheless, a 2025 Australian study found that "Chinese responses went from measured rejection of US messages to more explicit hostility" over the seven-year FONOP program from 2016-2023, concluding that the operations were "unsuccessful" in changing China's behavior and have only made the Chinese more defensive against the US.

Recent Philippine-China tensions

This week’s operation came a day after the Philippines accused Chinese vessels of "dangerous manoeuvres and unlawful interference" during a supply mission near the atoll. Manila also reported that two Chinese vessels collided, marking the first known incident of its kind in the area.

China’s coast guard said it had taken "necessary measures" to expel Philippine vessels from Chinese waters.

The Scarborough Shoal and the broader South China Sea remain contested by multiple countries, including Brunei, Indonesia, Malaysia, the Philippines, Taiwan, and Vietnam. Despite differences, China and ASEAN states have been working toward a Code of Conduct to manage disputes, with negotiations ongoing since 2018.