Response to Japan's provocations in East China Sea 'proper and restrained': MOD

China has taken "proper and restrained measures" in response to Japan's latest aggression of sending fighter jets and carrying out extensive surveillance over the East China Sea, said the Ministry of National Defense (MOD) Thursday.

Tension over the East China Sea has escalated again as multiple Japanese planes Wednesday entered China's East China Sea Air Defense Identification Zone (ADIZ) and carried out a prolonged surveillance, causing China to react with "necessary tracking and monitoring," air force spokesperson Shen Jinke was quoted as saying on the defense ministry website.

The spokesman also said it has taken "reasonable, proper and restrained measures" to cope with the threat in the airspace when Japanese F-15 fighter jets twice shadowed Chinese aircraft patrolling over the waters.

Tension over the long-running territorial dispute has been high between the two Asian countries in recent months, with each accusing the other of approaching too close to its own jets.

Zhou Yongsheng, a professor of Japan studies at China Foreign Affairs University interpreted Japan's latest move as a political message trying to prove it has the ability to cast influence over the territory.

"It serves both the political and military purpose of testing China's reactions as well as its capacity of defense in the region," Zhou told the Global Times.

"The scale of intrusion this time is one of the biggest since China established the ADIZ," Wang Xiaopeng, a maritime border expert at the Chinese Academy of Social Sciences said.

Japan released a white paper on Tuesday that criticized China's establishment of the ADIZ in the East China Sea.

Wang believes Japan's move is intended to attract international attention, as well as to unite other claimants like Vietnam and the Philippines over other territories in dispute with China.

Chinese air force planes have been regularly patrolling the area since the ADIZ, including the Diaoyu Islands, was declared in December 2013.