The Philippines announced Sunday that it is deploying aircraft and ships to drive away Chinese research vessels conducting "illegal marine scientific research."
The decision comes after the Philippine Coast Guard detected four Chinese research vessels operating in the vicinity of Philippine waters, according to the local English daily Philstar.
"We will not tolerate any illegal marine scientific research conducted without our government's consent. We are deploying aircraft and vessels to challenge and drive away these unauthorized vessels to protect Philippine sovereignty and sovereign rights," said Philippine Coast Guard commandant Admiral Ronnie Gil Gavan.
China's state-run news agency Xinhua also reported that on Sunday, "five Philippine crew members illegally landed on Tiexian Jiao of China's Nansha Qundao, in disregard of the Chinese side's repeated dissuasion and warnings," citing sources.
Beijing refers to the Spratly Islands in the South China Sea as the Nansha Qundao.
China Coast Guard law enforcement officers "identified the intruders and handled the incident in accordance with the law, effectively safeguarding China's territorial sovereignty and maritime rights and interests," it added.
