TOKYO -- A Chinese marine research vessel in July twice strayed into what Japan considers its exclusive economic zone without giving advanced notice as Tokyo says is required by international law. The intrusions came in the East China Sea, where EEZs overlap and official boundaries have yet to be set.
China has been ratcheting up similar activities in the body of water since 2010 but has recently become more aggressive. The incidents are viewed in some quarters as acts of coercion designed to alter the status quo in Northeast Asia.
