A Russian military plane flew directly from Moscow to Pyongyang on Tuesday, according to flight tracker data, in an unannounced trip that follows Kim Jong Un’s recent visit to Russia.

The Ilyushin Il-62 VIP passenger plane with tail number RA-86559 previously made another unannounced trip to Pyongyang for around 36 hours in early August, days after Russian defense chief Sergei Shoigu’s visit to the North Korean capital.

Russia has not revealed the purpose of either flight, but Tuesday’s visit comes as the two countries have openly pushed to expand military cooperation, raising the possibility that the plane brought military