China has conducted naval exercises near a group of disputed islands that has strained tensions between Beijing and Tokyo. Japan held naval exercises off its coast on Sunday.
China deployed 11 ships and eight planes from its navy, saying its exercises were aimed at protecting its "territorial sovereignty and maritime interests."
The daylong exercises in the East China Sea had been announced late Thursday by the state news agency Xinhua and posted on the Defense Ministry's website.
"They (exercises) will test the emergency-response capabilities of navy vessels, and ensure that maritime law enforcement remains strong," said Rear Admiral Shen Hao, according to the website of state-run China Radio International.
China Central Television said the exercises had started, but did not indicate where exactly in the sea they had taken place.
Disputed islands strain ties
Regional tensions between Beijing and Tokyo have escalated in recent months in a long-running diplomatic row over the chain of disputed islands in the East China Sea. Japan administers the Senkaku Islands, but China also claims them. Beijing calls the islands the Diaoyus. They are surrounded by sites thought to be rich with oil and natural gas deposits.
Tokyo nationalized the islands in September by buying them from their private Japanese owners. The move touched off a wave of anti-Japanese protests in China. The Japanese government said on Friday that it was observing the naval exercises.
"We decline to comment on the drill, but we will continue monitoring various Chinese moves," said Osamu Fujimura, Japan's chief cabinet secretary.
Meanwhile, Xinhua said on Friday that the producers of the Chinese film "Feng Shui" had pulled the movie from the Tokyo International Film Festival in protest over the island row.
But the festival's secretariat said it still plans to screen the film, because the withdrawal had not been formally submitted.
Feng Shui was the only Chinese-language film nominated for the festival's grand prize.
slk/ipj (AFP, dpa)