Chinese coast guard ships fired water cannons at two Philippine patrol vessels Tuesday near a disputed shoal in the South China Sea, damaging both in the latest flare-up in an increasingly tense territorial conflict.

There were no immediate reports of injuries in the incident off Scarborough Shoal, one of two hotly disputed areas where confrontations between China and the Philippines have flared on and off since last year.

A Philippine coast guard ship and an accompanying fisheries vessel were patrolling the waters off Scarborough Shoal when four Chinese coast guard ships, backed by six suspected militia ships, executed dangerous blocking maneuvers, Philippine coast guard spokesperson Commodore Jay Tarriela said.

PHILIPPINES ISSUES ‘STRONGEST PROTEST’ AFTER CHINESE WATER CANNON ASSAULT ON NAVY BOAT

A Chinese coast guard ship used a water cannon against the fisheries vessel, the BRP Bankaw, and two other Chinese coast guard ships hit the Philippine coast guard ship, the BRP Bagacay, simultaneously from both sides, damaging part of its deck railing and a canopy, Tarriela added.

“China’s coast guard and maritime militia vessels harassed, blocked and rammed vessels of the Philippine coast guard and the Bureau of Fisheries and Aquatic Resources,” a Philippine government task force dealing with the territorial disputes said.

The Philippine fisheries vessel sustained damages, including to its electrical, navigation and radio systems, the task force said. A number of journalists who were invited to join the patrol witnessed the hostilities, it added.

“China’s latest illegal and irresponsible behavior highlights its egregious disregard for the Philippines’ lawful exercise of its rights and entitlements in our own Exclusive Economic Zone,” the task force said.

The Philippine vessels pressed on with their patrol despite the Chinese coast guard’s actions, according to the Philippine coast guard. “They were not deterred and would persist in carrying out their legitimate operations to support Filipino fishermen and ensure their safety,” it added.

China called its action Tuesday a “necessary measure”. “The Philippines has violated China’s sovereignty with its actions,” said Gan Yu, spokesperson for China’s coast guard. “It will continue to carry out actions to defend its rights in the Chinese waters according to law, and will resolutely uphold our country’s maritime rights”, he insisted.

The Chinese coast guard has also re-installed a floating barrier across the entrance to the shoal’s vast fishing lagoon. The Philippine coast guard removed a similar barrier in the past to allow Filipinos to fish there.

China insists on its sovereignty over virtually all of the South China Sea, a key global trade route.

In addition to the Philippines and China, Vietnam, Malaysia, Brunei and Taiwan have also been involved in the territorial disputes.

The increasing frequency of the skirmishes between the Philippines and China, which have injured Filipino navy personnel and damaged supply boats in the past, has sparked fears the territorial conflict could degenerate into an armed confrontation that could put China and the United States on a collision course.

The U.S. lays no claims to the South China Sea but has warned that it is obligated to defend the Philippines, a longtime treaty ally, if Filipino forces, ships and aircraft come under an armed attack including in the contested waters.