MANILA, May 7 — The Philippine Coast Guard said today it deployed aircraft to issue radio warnings to a Chinese research ship in a disputed area of the South China Sea “swarming” with vessels from Beijing’s so-called maritime militia.

The research vessel Xiang Yang Hong 33, which is capable of supporting submersible craft, was operating near a reef in the contested Spratly Islands chain, the Philippine Coast Guard said.

The Chinese ship was deploying a service boat towards the Spratlys’ Iroquois Reef yesterday when it was spotted by a Coast Guard plane, “confirming ongoing unauthorised (marine scientific research) operations”, it said in a statement.

Iroquois Reef is located at the southern end of Reed Bank, an area in the Spratlys thought to be rich in natural gas and oil.

During the flight, Manila’s Coast Guard also spotted 41 “maritime militia vessels” anchored in waters surrounding Iroquois Reef and Philippine-occupied Thitu Island, home to about 400 Filipinos and a new coast guard station.

“The Philippines has not granted such consent to the (People’s Republic of China) for any (marine scientific research) activities in these waters,” the Coast Guard said.

“The presence of the research vessel and the large-scale swarming by Chinese Maritime Militia vessels represent a serious infringement on Philippine sovereign rights and maritime jurisdiction.”

Beijing’s embassy in Manila pointed to its “historic rights” and said in reply that the relevant islands and reefs in question were Chinese territory.

It said China’s scientific research vessels conducted each of their missions in accordance with international law.

The Xiang Yang Hong 33, which left China more than three weeks ago, has been monitored conducting surveys near various Philippine-claimed features in the Spratlys, including the flashpoint Sabina Shoal and Second Thomas Shoal.

Beijing claims almost the entire South China Sea, despite an international ruling that its assertion has no legal basis, and defends its actions against Philippine vessels as lawful and proportional.

It has been deploying navy, coast guard and maritime militia forces — allegedly Chinese fishing vessels — in a bid to bar the Philippines from strategically important reefs and islands in the disputed waterway. — AFP

A Taiwanese government minister has made a rare visit to a Taiwan-controlled island in the hotly contested South China Sea, as the coast guard held drills including a simulated boarding of a suspect vessel.

Taiping island, also known as Itu Aba, is the largest in the disputed Spratly archipelago, which is also claimed by China, the Philippines and Vietnam.

Ocean Affairs Council Minister Kuan Bi-ling visited Taiping on Tuesday, the Coast Guard Administration said in a statement on Wednesday.

Kuan is the first Taiwanese government minister to set foot on the island in seven years, Taiwan’s Central News Agency reported.

Taiwan’s coast guard held exercises during Kuan’s visit, including armed special forces practice boarding a suspicious cargo ship that had failed to respond to calls.

In another drill, coast guard personnel carried out a humanitarian emergency rescue operation.

The defence ministry also dispatched a C-130 transport aircraft to join the exercises.

To assert its claim on Taiping, Taiwan has installed a solar-powered lighthouse, an airstrip and a pier.

The island covers about 0.51 square kilometres (0.19 square miles) and most of its inhabitants work for the coast guard.

Taiwan has rejected a 2016 ruling by the Permanent Court of Arbitration in The Hague, which was brought by the Philippines against China over the South China Sea.

The tribunal found China’s claims to almost the entire waterway had no legal basis.

It also stated that Taiping was legally a “rock” and not entitled to its own exclusive economic zone, undermining Taiwanese claims to waters surrounding the island.

Taiwan’s government rejected the court’s ruling, saying it “severely jeopardised” Taiwan’s rights.

It said the judgement has no legally binding force since the tribunal did not formally invite Taipei to take part in its proceedings or solicit its views.

The Philippines accused Chinese fishermen on Monday of pouring cyanide in waters in the Spratly Islands, a flashpoint in the disputed South China Sea that has been the site of violent confrontations with Chinese vessels.

Beijing claims the strategic South China Sea in nearly its entirety, despite an international ruling that its assertion has no legal basis.

The Philippines’ National Security Council (NSC) alleged the poisoning began last year around Second Thomas Shoal in the Spratly chain, which sits near vital shipping lanes and is reputedly rich in minerals.

“The use of cyanide on Ayungin Shoal is a term of sabotage that seeks to kill local fish populations, depriving Navy personnel of a vital food source,” NSC assistant director-general Cornelio Valencia told a news conference, using the Philippines’ term for the reef.

These actions also “threaten our Navy personnel” through exposure to contaminated water, eating poisoned fish, as well as eroding corals, Valencia added.

Manila and Beijing have a long history of maritime territorial disputes in the hotly contested waterway, including a violent clash in June 2024 in which Chinese coastguard personnel wielding knives, sticks and an axe boarded Philippine Navy boats.

Valencia said Manila raised the alleged poisoning with Beijing at a recent meeting but has received no formal reply.

The Chinese embassy did not immediately respond to AFP’s requests for comment on Monday.

Valencia said that reef damage from cyanide poisoning could also compromise the structural foundations of the BRP Sierra Madre, a World War II-era warship on which the Filipino troops are stationed.

Manila deliberately grounded the vessel on the shoal in 1999 to stake its claim to the territory.

Philippine Navy spokesman Rear Admiral Roy Vincent Trinidad said Filipino troops had seized 10 bottles of cyanide from sampan boats launched from Chinese fishing ships in February, July and October 2025.

He said that soldiers observed another Chinese sampan crew poisoning waters near the shoal last month, adding that the shoal’s waters later tested positive for cyanide.

None of the troops aboard the warship have tested positive for the poison, Trinidad added.

Valencia and Trinidad both alleged the fishermen’s mother ships worked for the Chinese Navy.

Valencia said the NSC planned to submit a report next week to the Philippine foreign ministry which could become the basis for a diplomatic protest.

Manila has also ordered the navy and coastguard to step up patrols “to prevent further environmental harm” in the area, he added.