The Chinese military is in turmoil in the contested Scarborough Reef, while the Philippines holds war games with the US and other Western allies.

The Chinese military has launched military exercises near an area in the South China Sea over whose sovereignty it disputes with the Philippines.

The Southern Theater Command said on Wednesday it had conducted air and sea combat patrols “near Huangyan Island” – the Chinese name for the Scarborough Reef – to test “attack capabilities.” The drills appear to be in response to military maneuvers conducted the same day by the United States, Australia, Canada and the Philippines.

The maneuvers tested the reconnaissance and early warning capabilities of the Chinese troops, Beijing said.

“All military activities that disrupt the South China Sea, create flashpoints and undermine regional peace and stability will be controlled to the best of our ability,” it said.

In a joint statement, military chiefs from the United States, Australia, Canada and the Philippines said they “stand together to address common maritime challenges and underscore our shared commitment to upholding international law and the rules-based order.” They said the two-day exercises were being held to maintain unimpeded passage in the Asia-Pacific region.

Stalemate

A tense standoff has been going on between Beijing and Manila for months as China continues to lay claim to almost the entire South China Sea despite an international tribunal ruling that its claims lack any legal basis.

Scarborough Shoal is located 240 km (150 miles) west of the Philippine main island of Luzon and nearly 900 km (560 miles) from the nearest major Chinese landmass, Hainan.

In 2012, China dispatched coast guard vessels to take control of the shoal, a triangular chain of reefs and rocks that are part of a rich fishing ground and have long served as a safe haven for Filipino fishermen.

The dispute also focused on a warship that Manila has been running aground on the controversial Second Thomas Reef for years.

In June, Chinese coast guards armed with knives and axes boarded Philippine warships near the strategic reef. One sailor lost a thumb and Philippine equipment was confiscated or destroyed.

Beijing blamed Manila for the escalation and stressed that its measures to protect its claims were legal and proportionate.

Last month, the United States said it would provide the Philippines with an additional $500 million in military funds to counter Beijing’s growing assertiveness in the region.

Beijing responded that “courting countries outside the region to provoke confrontation … will only undermine regional stability and exacerbate tensions.”

The investment will “only lead to greater uncertainty” in Manila, they warned.

In addition to China and the Philippines, Vietnam, Malaysia, Brunei and Taiwan are also involved in separate but increasingly tense territorial disputes over the waterway, which is seen as a potential flashpoint and sensitive fault line in the regional rivalry between the United States and China.

The US military has been using naval vessels and fighter jets for decades as part of the so-called freedom of navigation and for night patrols. China rejects this and sees it as a threat to regional stability.