China said it sent some of its most advanced fighter jets and an early warning aircraft into its new air-defense zone on Thursday, after Japan and South Korea said they had dispatched military planes to the area over the past few days without notifying Beijing.

China's defense ministry also dialed back its warnings over the zone, sending mixed signals that analysts and diplomats said were designed to address international concerns at the same time as satisfying domestic demands for a strong response to incursions.

A defense ministry spokesman said China had "identified" all foreign aircraft entering the Air Defense Identification Zone that was established on Saturday over an area covering islands at the center of a fierce territorial dispute between Tokyo and Beijing.