The Philippine Coast Guard believes a Chinese research vessel may have deployed an instrument in the waters off Batanes during what Manila regards as unauthorized marine scientific research. Rear Adm. Jay Tarriela, the Coast Guard's spokesperson for the West Philippine Sea, laid out that assessment on Saturday. The conclusion came after authorities monitored the vessel, identified as the Jia Hai, while it operated in the area. Foreign marine scientific surveys inside the Philippine exclusive economic zone require the government's consent, and the Coast Guard maintains none was requested. Teams have been watching the ship closely to work out what it placed in the water and whether it can be documented or recovered. The encounter is only the latest involving Chinese government vessels in waters the Philippines claims as its own. Batanes, the country's northernmost province, has become a frequent flashpoint because it sits near busy shipping lanes.