BEIJING -- The Chinese People's Liberation Army (PLA) Southern Theater Command on Saturday conducted a joint sea-air patrol in the South China Sea, a spokesperson said on Sunday, noting that the armed forces stay on high alert for any destabilizing activities in the region.

Tian Junli, the spokesperson, said the Philippines' attempt to rally extraregional countries to carry out so-called "joint patrols" had heightened security risks and undermined peace and stability in the South China Sea.

All military activities that seek to stir up trouble or create flashpoints in the region are under full control, Tian added.