Air Defence Identification Zone
The Air Defense Identification Zone is airspace over land or water in which the ready identification, location, and control of civil aircraft over land or water is required in the interest of national security. China's Defence Ministry announced its ADIZ over a vast area in the East China Sea on November 23, 2013, which covers the area around the Diaoyu islands, controlled by Japan and known as the Senkaku Islands. The establishment of this zone drew strong opposition from Japan, the US and South Korea, becoming a flashpoint in East Asian politics and security.
US deploys new surveillance planes in Japan amid territorial row with China
The US Navy has deployed a pair of sophisticated surveillance aircraft to Japan, officials said, with four more due to arrive this week amid rising tension over China's territorial claims in the region.
Two P-8A Poseidon jets arrived at Kadena air base in Okinawa on Sunday, in a move that was planned before Beijing declared an air defence identification zone last month covering disputed islands in the East China Sea, a navy official said.
"This was scheduled for a long time," said the official, who spoke on condition of anonymity. "It's a rotational deployment."
The other four were expected to arrive there later this week, a navy spokeswoman said.
The assignment to Japan marks the first mission for the new plane, which is replacing the propeller-driven P-3 Orion aircraft that dates back to the 1960s.
The P-8A planes, converted Boeing 737s equipped with advanced radar and anti-ship missiles, are designed to hunt submarines and other vessels.
"The P-8A is the most advanced long-range anti-submarine and anti-surface warfare aircraft in the world," the Pentagon said.