TOKYO - Three Chinese coastguard ships on Tuesday entered disputed waters near East China Sea islands at the centre of a bitter row with Tokyo, Japanese officials said.
The vessels sailed into the 12-nautical-mile band around the Tokyo-controlled Senkaku islands - which Beijing calls the Diaoyus - at around 0030 GMT, the Japanese coastguard said.
The incursion came a day after Japan's defence minister said Tokyo could be a key participant if conflict breaks out in Asia as he warned China was seeking to exploit difficulties between allies.
It was the latest in a series of forays by Chinese ships in a year-long spat between Tokyo and Beijing that has sent relations plummeting.
The islands - believed to harbour vast natural resources below their seabed - are seen as a potential flashpoint that some observers fear could lead to armed conflict between the Asian giants.