BEIJING, China: Tensions between China and the Philippines flared again this week after a confrontation near the contested Scarborough Shoal in the South China Sea, with both sides trading accusations over an incident involving coast guard vessels. China's coast guard accused a Philippine ship of deliberately colliding with one of its vessels in waters Beijing calls Huangyan Island. The Philippine coast guard reported that two Chinese ships fired water cannons at the BRP Datu Gumbay Piang for nearly half an hour. The incident came less than a week after Beijing announced that it was designating part of Scarborough Shoal as a national nature reserve. Adding to the tensions, the Philippine coast guard said a Chinese navy warship broadcast a warning over the radio announcing live-fire exercises in the area.