Photo/Illutration In this screen grab from video provided by the Armed Forces of the Philippines, a Chinese coast guard ship uses water cannon on a Philippine resupply vessel Unaizah May 4 as it approaches Second Thomas Shoal, locally called Ayungin shoal, at the disputed South China Sea on Saturday, March 23, 2024. (Armed Forces of the Philippines via AP)

MANILA--Two Chinese coast guard ships fired at a Philippine supply boat with water cannon Saturday in the latest confrontation near a disputed South China Sea shoal, causing heavy damage to the wooden vessel, Philippine officials said.

It was not immediately clear if the Philippine navy crew was injured, or whether their damaged boat, the Unaizah May 4, managed to maneuver past the Chinese coast guard blockade to deliver supplies to Philippine forces manning a territorial outpost in the nearby Second Thomas Shoal. It's the second time this month the Unaizah May 4 has been damaged during an attempt to resupply the outpost.

The shoal has been occupied by a small contingent of Philippine navy personnel on a marooned warship since the late 1990s, but has recently been surrounded by Chinese coast guard and suspected militia vessels in an increasingly tense territorial standoff.

Aside from China and the Philippines, Vietnam, Malaysia, Taiwan and Brunei also have overlapping claims in the resource-rich and busy waterway, a key global trade route. The United States lays no claims to the strategic waters but has deployed Navy ships and fighter jets in what it calls “freedom of navigation” operations, which have been criticized by China.

A Philippine coast guard ship that was escorting the Unaizah May 4 was also blocked and surrounded by a Chinese coast guard ship and two suspected militia vessels, Philippine coast guard spokesperson Commodore Jay Tarriela said.

The escort ship, BRP Cabra, was "isolated from the resupply boat due to the irresponsible and provocative behavior of the Chinese maritime forces,” Tarriela said, adding that the Chinese forces were disregarding international regulations aimed at preventing collisions at sea.

Video released by the Philippine military shows two Chinese coast guard ships hitting a smaller wooden-hulled boat with high-pressure water cannon sprays at close range, causing the boat to shift in the high seas.

The Philippine military said without elaborating that its chartered boat “sustained significant damage.”

There was no immediate statement from Chinese officials in Manila or in Beijing.

Chinese coast guard previously blasted the Unaizah May 4 with high-pressure water cannon blasts in a confrontation near the Second Thomas Shoal on March 5, shattering its windshield and slightly injuring a Filipino admiral and four of his men with glass shards and splinters of debris.

Beijing said then that its coast guard ships had taken steps after the Philippine vessels ignored warnings and encroached into what it calls its territorial waters.

The Department of Foreign Affairs in Manila summoned China’s deputy ambassador after the March 5 confrontation to convey a protest against the Chinese coast guard’s actions, which it said were unacceptable.

Washington renewed a warning that it is obligated to defend the Philippines, its oldest treaty ally in Asia, if Filipino forces, ships and aircraft come under an armed attack, including in the South China Sea. China has asked the U.S. to stop meddling in what it calls a purely Asian dispute.