A North Korean aircraft, which may be a fighter jet, has crashed in China near the country's shared border, say Chinese and South Korean reports.
It is believed the pilot, who was killed, may have been trying to defect to Russia, according to unnamed intelligence sources cited by Yonhap.
The crash happened on Tuesday afternoon in Fushun county, Liaoning province.
Defections are common but an attempt by plane is highly unusual and would be a source of embarrassment for Pyongyang.
China has a repatriation agreement with North Korea, which could explain why the pilot may have been trying to reach Russia, the report added.
North Korea has a military airbase in Sinuiju, near the border with China.
China's state media confirmed an unidentified small plane had crashed and that it may belong to North Korea.
An investigation into the cause of the crash was under way, Xinhua reported.
Photographs of the wreckage reportedly taken by a local resident and posted on the internet showed North Korea's insignia on the plane's fuselage.
Military experts said the plane appeared to be a Soviet-era fighter jet.
A report in Hong Kong's Ming Pao newspaper said that a second pilot had bailed out but gave no information on his whereabouts. It conflicts with the South Korean report of only one pilot on board.
Technically, North and South Korea remain at war although a ceasefire agreement ended the Korean War of 1950-53.
Their border is the most heavily militarised zone in the world.