The Philippines today accused China’s coast guard of harassment and damaging one of its boats in a disputed area off the South China Sea.

The Philippine coast guard said its two vessels stood their ground at the Scarborough Shoal, a key battleground in the South China Sea, but one sustained damage from use of water cannon by two Chinese coast guard ships.

No country has sovereignty over the strategically located Scarborough Shoal, a prime fishing patch used by several countries and close to major shipping lanes. The shoal falls inside the Philippines’ exclusive economic zone.

China and Philippines previously said they would seek better communications and management around skirmishes in the vast South China Sea, but tensions have increased recently, as the Philippines forges stronger diplomatic and military ties with its ally, the United States.