TOKYO - The Japanese Ground Self-Defense Force's intelligence unit secretly profiled citizens using a wide-ranging checklist that included beliefs, ideologies and sexual preference, raising possible violations of the personal information protection law, former troop members and other sources said Wednesday.

The unit based in Camp Asaka in Tokyo systematically collected the data without its members revealing their identities and compiled it into a report, justifying the practice as needed to understand the beliefs and principles of potential collaborators, the sources said.

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