-5- The menace of Japanese aggression against Mongolia became especially strong and direct after the seizure of Manchuria by Japan in 1931. Though the Mongolian People’s Republic had no and could have no aggressive intentions against Manchukuo, the Japanese militarists under the pretext of strengthening border guards of Manchukuo created entire military zones on the frontiers of the Mongolian People’s Republic, built railway lines, highways and lines of communication for the jump to the territory of the Mongolian People’s Republic turning it into the military base for the offensive against the Soviet Union in the North and China in the South. To realize that plan Japanese invaders fabricated false maps which were supposed to prove that certain Mongolian frontier areas belonged to Manchukuo. The events connected with the seizure by Japanese imperialists of Mongolian territory of Halhin-Sumey and Pulun-Derisu in the area of lake Buir-Nur in 1935-1936 were the beginning of the new open armed aggression against Monglian People’s Republic. On January 24, 1935 Japanese-Manchurian troops attacked the Mongolian outpost in the district of Halhin-Sumey. The garrison of the outpost was massacred and the buildings burnt down.