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.

Asked about the report in press conferences earlier this year, Defense Minister Shinjiro Koizumi did not admit to its existence, simply saying, "We have not confirmed any inappropriate activities."

The intelligence unit was established at the GSDF in 2007 to gather information and build local networks after the Self-Defense Forces experienced difficulties in collecting information on local security conditions during the SDF's dispatch to Iraq from 2003 to 2009.

The unit is reportedly composed of around 50 personnel, headed by a lieutenant colonel.

Unit members were assigned to different areas such as Africa and Southeast Asia and tasked to collect information. They contacted restaurant owners residing in Japan who were from the countries assigned to the unit members, as well as Japanese researchers, according to the sources.

While researching the situation in the countries, the members also collected personal information of the contacts and recorded them in a "Personal Basic Source Data" report, the sources said.

The data were collected under a total of 41 checklist items that also included physical features, addresses, phone numbers, place of employment and financial situation, the sources said.

But in practice, many fields were left blank, they said. One of the sources said the report was compiled by referencing the investigation items used by a unit in the U.S. military.

The personal information protection law bans administrative entities from acquiring personal information by deception or other wrongful means.

The report was stored within the intelligence unit by a group known as "source control" but was not handled as an official document. It may potentially violate the public records management law, which stipulates the proper management of administrative records, they said. It is not clear to what level within the SDF such reports were shared.

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