Japan, South Korean military planes defy China's new defence zone

A group of disputed islands known as Senkaku in Japan and Diaoyu in China is seen from the city government of Tokyo's survey vessel in the East China Sea in this September 2, 2012 file photo. REUTERS/Chris Meyers/Files

TOKYO/SEOUL (Reuters) - Japanese and South Korean military aircraft flew through disputed air space over the East China Sea without informing China, officials said on Thursday, challenging a new Chinese air defence zone that has increased regional tensions and sparked concerns of an unintended clash.

The move came after Tokyo's close ally Washington defied China's demand that airplanes flying through its unilaterally announced zone identify themselves to Chinese authorities, flying two unarmed B-52 bombers over the islands on Tuesday without informing Beijing.