From Al Jazeera:

Chinese vessels have challenged a Philippine military plane on patrol over disputed waters in the South China Sea, according to the Philippine military.

The Islander aircraft was flying over Subi Reef on April 19 when a Chinese vessel radioed a warning, Brigadier-General Joselito Kakilala, a Philippine military spokesperson, said on Sunday.

From Fox News:

The Philippines on Sunday urged the 10-member Association of Southeast Asian Nations to take immediate steps to halt land reclamation by China in the disputed waters of the South China Sea, warning that failure to do so will see Beijing take “de facto control” of the area.

Philippine Foreign Secretary Albert del Rosario told a meeting of ASEAN foreign ministers that if China’s construction of artificial islands on reefs claimed by other countries is allowed to be completed, then Beijing will impose its claim over more than 85 percent of the sea.