The Mitsubishi Ki-21, formal designation "Type 97 Heavy Bomber" was a Japanese heavy bomber during World War II. It began operations during the Second Sino-Japanese War participating in the Nomonhan Incident, and in the first stages of the Pacific War, including the Malayan, Burmese, Dutch East Indies and New Guinea Campaigns. It was also used to attack targets as far-flung as western China, India and northern Australia. The Allies designated it under the reporting names "Sally" /"Gwen".
Mitsubishi Ki-21
Ki-21 of the Daisan Dokuritsu Hikōtai at Yontan Airfield, 25 May 1945
The Battles of Khalkhin Gol were the decisive engagements of the undeclared Soviet–Japanese border conflicts involving the Soviet Union, Mongolia, Japan and Manchukuo in 1939. The conflict was named after the river Khalkhin Gol, which passes through the battlefield. In Japan, the decisive battle of the conflict is known as the Nomonhan Incident after Nomonhan, a nearby village on the border between Mongolia and Manchuria. The battles resulted in the defeat of the Japanese Sixth Army.
Japanese infantrymen near wrecked Soviet armored vehicles, July 1939
Mongolian cavalry in the Khalkhin Gol (1939)
Mongolian troops fight against a Japanese counterattack on the western beach of the river Khalkhin Gol, 1939
Japanese soldiers cross the Khalkhin Gol