Beijing hit back Thursday at Tokyo's claims of "dangerous" flying near disputed islands, accusing Japanese fighter jets of coming recklessly close to a Chinese aircraft last year.

Two Japanese F-15 fighter planes came within 10 metres of a Chinese Y-8 transport aircraft over the East China Sea on November 23, defence ministry spokesman Geng Fusheng said, according to a transcript on the ministry's website.

"We conducted an effective response to dangerous Japanese close surveillance, and have conclusive evidence (of the incident)," he said.

Beijing raised tensions in November when it declared an air defence identification zone (ADIZ) covering the East China Sea, overlapping a similar Japanese zone and covering islands bitterly disputed between the two nations.

The Tokyo-controlled outcrops are known as Diaoyu in Chinese and Senkaku in Japanese.

Analysts have warned that increased patrols inside the zones raise the risk of accidents which could spiral into conflict.

A Japanese ministry spokesman on Sunday said a Chinese SU-27 jet flew within 30 meters of a Japanese OP-3C surveillance plane above the waters where the countries' ADIZs overlap.

"They were dangerous acts that could lead to an accident," Japanese Defence Minister Itsunori Onodera told reporters about the incident on Saturday.

China's defence ministry said two Japanese planes entered China's ADIZ, "interfering with joint naval exercises between China and Russia" for which a "no fly" notice had been issued.