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.

The incident marks the second confrontation this week between Manila and Beijing over disputed South China Sea islands.

A Chinese navy helicopter flew within 10 feet of a Philippine patrol plane on Tuesday in a disputed area of the the South China Sea, as the Filipino pilot warned by radio: “You are flying too close, you are very dangerous.