In the 1960s Japan and the ROC government had a secret deal to deport Taiwanese independence activists to Taiwan. Activists in Japan fighting against these deportations went on to found Amnesty International Japan in 1970
https://www.taipeitimes.com/News/feat/archives/2025/02/08/2003831523
"Given that Taiwan’s current government is committed to transitional justice, it should encourage its Japanese counterparts to make these files, including those of the Immigration Bureau and Police Foreign Affairs Division, available to the public."
"Processing this dark episode in the shared history of Taiwan and Japan can benefit both peoples and governments."