What happens in the South China Sea? 3:15

(CNN) -- A floating barrier installed by China to prevent Filipino vessels from fishing in a disputed area of the South China Sea has been removed, Philippine authorities said on Monday, in the latest flashpoint between Manila and Beijing over their competing maritime claims.

A video released by the Philippine Coast Guard on Monday showed a Filipino diver cutting what it said earlier was a 300-meter-long string of buoys near the Masinloc Low, also known as Scarborough Shoal, a small but strategic reef, and fertile fishing area 200 kilometers west of the Philippine island of Luzon.

The footage showed the diver wearing a simple mask and snorkel gliding beneath the waves and using a small knife to cut the rope after reaching the barrier on a rickety fishing boat with a small crew.

The video is a vivid illustration of a tense power struggle that has been unfolding for years in the South China Sea as Manila tries to cope with Beijing's increasingly assertive claims to the disputed strategic waterway.

  • Philippines accuses China of installing floating barrier in disputed South China Sea


Philippine authorities said Sunday that three Chinese Coast Guard ships and a Chinese maritime militia service ship had installed the barrier following the arrival of a Philippine government ship in the area.

"The barrier posed a danger to navigation, a clear violation of international law," the Philippine Coast Guard said in a statement Monday, adding that it also infringed on Philippine sovereignty.

At a regular press briefing on Tuesday, Chinese Foreign Ministry spokesman Wang Wenbin said "China is determined to safeguard its sovereignty and maritime interests over Huangyan Island," referring to the disputed sandbar by its Chinese name.

"We advise the Philippines not to make provocations or look for trouble," he added.

Beijing claims "undisputed sovereignty" over nearly all of the 3.3 million square kilometers of the South China Sea, as well as most of the islands and sandbars it contains, including many features that lie hundreds of kilometers away from the Chinese mainland.

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A small crew arrived at the barrier near Scarborough Shoal on a native fishing boat. (Credit: Philippine Coast Guard)

Over the past two decades, China has occupied several reefs and atolls across the South China Sea, building military facilities, including airstrips and ports, that have not only challenged the Philippines' sovereignty and fisheries, but also endangered marine biodiversity in this highly contested and resource-rich waterway.

In 2016, an international tribunal in The Hague ruled in favor of the Philippines in a landmark maritime dispute, which concluded that China has no legal basis to claim historic rights over most of the South China Sea.

Beijing has ignored the ruling.

Western maritime security experts, along with officials from the Philippines and the United States, have increasingly accused Beijing of using apparently civilian fishing vessels as a maritime militia that acts as an unofficial (and officially deniable) force that China uses to push its territorial control claims both in the South China Sea and beyond.

The situation comes days after the Philippine Coast Guard accused China's maritime militia of turning vast tracts of coral near the Palawan island chain into a bleached, broken wasteland.

China's Foreign Ministry dismissed those allegations as "false and baseless."

PhilippinesSouth China Sea