"Unlawful activities!": Philippines slams China for EEZ research vessel incursion

During the operation, the PCG reported spotting a manned deep-sea submersible, named the Shenhai Yongshi (Deep-Sea Warrior), which was retrieved by the Chinese vessel.

The submersible is capable of diving to 4,500 metres (2.8 miles) and is typically deployed for deep-sea exploration and scientific missions, the PCG said.

It said it also observed a rigid hull inflatable boat recovering a yellow-coloured, unidentified piece of equipment potentially linked to marine research.