Kyodo News revealed on Dec 30 that when 
authorities detained a Japanese woman — a former executive of a Japanese language school in her 60s — in Shanghai in 2015 when she was on a business trip, she was charged with engaging in spying activities in Japan, marking the first known case in which Japanese nationals’ actions in Japan became the basis for Chinese criminal prosecution. The government was aware that authorities had criminally charged her for activities in Japan but did not publicly release that information.
In 2012 and 2013, the woman met with an official at the Embassy in Tokyo multiple times and asked him how Beijing viewed the confrontation between the two Asian neighbors following Tokyo's decision to put the Senkakus under state control — the government purchased a main part of the Beijing-claimed islands from a Japanese individual in Sep 2012. She subsequently conveyed the diplomat's views to two government officials.
In Dec 2018, the Shanghai Intermediate People's Court sentenced her to 6 years for spying. In Feb 2019, the city's High People's Court ruled that while she had engaged in espionage, the information she sent to the Japanese government did not pertain to national security — not state secrets.

The high court, however, rejected her appeal and upheld the lower court's 6-year jail sentence and the confiscation of 50,000 yuan ($6,850). She was released after completing her sentence and returned to Japan in 2021.
There are concerns that authorities may have conducted information gathering activities in Japan to obtain evidence.
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