Over the past week, Chinese and Philippine vessels have engaged in multiple collisions and face-offs near Sabina Shoal, a disputed atoll lying just 86 miles from the Philippines’ west coast and 745 miles from China, which claims almost all of the South China Sea as its sovereign territory despite an international ruling to the contrary.

The violent confrontations came just weeks after Beijing and Manila struck a temporary deal to lower tensions that had been rising all summer at another nearby reef, where China’s increasingly aggressive tactics had raised alarm across the region as well as in Washington, a mutual defense ally of the Philippines.