China holds sea and air combat drills at the disputed Scarborough Shoal

BEIJING (AP) — China held sea and air combat drills Wednesday at the disputed Scarborough Shoal, an area of reefs and rocks the Philippines also claims in the South China Sea.

On Sunday, China published new baselines for the shoal including geographic coordinates. A nation’s territorial waters and exclusive economic zone are typically defined as the distance from the baselines.

“This is a patrol and guard activity carried out by the theater troops in accordance with the law,” the People’s Liberation Army’s southern command said in a short statement.

China seized the shoal, which lies west of the main Philippine island of Luzon, in 2012 and has since restricted access to Filipino fishermen there. A 2016 ruling by an international arbitration court found that most Chinese claims in the South China Sea were invalid but Beijing refuses to abide by it.

Tensions between the two countries have been building over their competing claims to Scarborough Shoal and other outcrops in the sea, and clashes have occurred in the disputed waters including the Chinese coast guard firing water cannons at Filipino ships.

Philippine President Ferdinand Marcos Jr. signed two laws last week reaffirming the extent of his country’s maritime territories and right to resources, including in the South China Sea, in a move that angered China.

China’s claims to almost the entire sea overlap with claims by the Philippines, Vietnam, Indonesia and other governments.