BEIJING - China's Defence Ministry said on Wednesday it had monitored the entire progress of two unarmed US B-52 bombers that flew over disputed islands in the East China Sea on a training mission without informing Beijing.The US move was in defiance of China's declaration of a new airspace defense zone, and raised the stakes in a territorial standoff."The Chinese air force monitored the entire course and identified (them) in a timely way, ascertaining that they were US aircraft," the ministry said in a statement on its website."The Chinese side has the ability to effectively manage and control the relevant airspace," it added.