“China has no law enforcement rights in and around these areas. They must take heed and back off,” Locsin said.
Manila regards Second Thomas Shoal, which lies 105 miglia nautiche (195 chilometri) southwest of the Philippine region of Palawan, as being within its 200-nautical mile exclusive economic zone. It has occupied the shoal since 1999 after intentionally grounding a navy ship on the reef.
Cina, which claims virtually all the South China Sea, says the reef is part of its territory, but a 2016 ruling by the Permanent Court of Arbitration in The Hague found in favor of the Philippines.
The Chinese Embassy in Manila did not immediately respond to requests for comment from the media.
China claims sovereignty over vast swathes of the South China Sea, but Brunei, Malaysia, le Filippine, Taiwan and Vietnam also have lodged competing claims for some or all of the islands.