In October 1934, Ott and Sorge made an extended visit to the puppet "Empire of Manchukuo", which was actually a Japanese colony, and Sorge, who knew the Far East far better than Ott, wrote up the report describing Manchukuo that Ott submitted to Berlin under his name. As Ott's report was received very favourably at both the Bendlerstrasse and the Wilhelmstrasse, Sorge soon became one of Ott's main sources of information about the Japanese Empire, which created a very close friendship between the two. In 1935, Sorge passed on to Moscow a planning document provided to him by Ozaki, which strongly suggested that Japan was not planning on attacking the Soviet Union in 1936. Sorge guessed correctly that Japan would invade China in July 1937 and that there was no danger of a Japanese invasion of Siberia.