According to Marine AIS (Automatic Identification System), a huge Chinese towing ship with shipboard number 19016 is parked in northwest side of Ayungin Shoal, waiting for further instructions. It is accompanied by two Chinese fishing vessels. A China Coast Guard ship is also nearby.

China claims that the Philippine retired warship BRP Sierra Madre illegally grounded and occupied the Shoal since 1999. The Philippines maintains that Ayungin Shoal is part of the exclusive economic zone and continental shelf of the country.