North Korean leader Kim Jong-un's private plane has been spotted in the Siberian port of Vladivostok.
According to tracking website Flightradar24, Kim's plane arrived in Vladivostok on Monday morning and returned to North Korea three hours later. The plane flew over North Korea without using a call sign until it reached the East Sea.
The elderly Ilyushin 62M aircraft was not used to take Kim to Singapore and China last month because it can only cover short distances.
Kim has not been seen in public since visiting factories in Sinuiju early this month, raising speculation that he may have flown to Russia. He missed a friendly basketball match with South Korean players last week and did not meet U.S. Secretary of State Mike Pompeo over the weekend.
He also seems to have missed a ceremony at the Kumsusan Palace of the Sun in Pyongyang on Sunday commemorating the 24th anniversary of the death of nation founder Kim Il-sung, or at least state media did not say he was there.
But a Unification Ministry official said if the plane returned within just three hours "there is very little chance of Kim Jong-il being on board. Considering that the plane landed in Vladivostok, the trip appears to be related to the upcoming Eastern Economic Forum in September."
Russian President Vladimir Putin has invited Kim to the forum, and lower-ranking officials may have used the plane to prepare for his visit.
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