A Chinese military helicopter flew within 10 feet (3 meters) of a Philippine patrol plane over the South China Sea on Tuesday, in what observers said was the second incident of potentially catastrophic behavior by the People’s Liberation Army against foreign aircraft in a week.

A Philippine plane warned a Chinese military helicopter over the South China Sea that it was "flying too close," as tension between the U.S. ally and Beijing soars.

China’s military said it drove away three Philippines aircraft “illegally” flying over the disputed Spratly Islands, marking the second aerial incident this week involving Beijing and Manila in the South China Sea.