More than 200 Chinese militia vessels have swarmed near a Philippine-occupied island in the most hotly disputed region in the South China Sea.

The Philippino Department of Foreign Affairs lodged an official protest after 275 Chinese fishing-militia and military-controlled Coast Guard vessels appeared near Thitu Island.

According to military officials, the Chinese vessels have been sighted more than 600 times in the region this year alone. Concerns have been raised as the vessels don’t appear to be doing anything other than occupying the waters.