Police in Tokyo have been monitoring activities of Muslims in Japan since 2008, a new report revealed.

The Japanese police monitors Muslims in Japan only based on their religion alone. A court case has recently challenged the constitutionality of this surveillance program, but it was denied.

Japan’s Supreme Court denied the case on May 31, 2016 even though surveillance based on religion or ethnicity is illegal under Japan’s constitution.

Japan’s constitution supports the right to privacy, equal protection under the law, and freedom of religion.

The fact that the Japanese police have been monitoring activities of Muslims firs became public in 2010, after more than 100 internal Metropolitan Police Depart documents were leaked.

The leaked documents included the names, addresses and other personal information of Muslims living in Japan. Apparently the surveillance was set years before 2010, and was motivated by security arrangements for the 2008 G-8 summit held in Japan.

According to Japan Times, the leak revealed that the police had compiled detailed profiles on 72,000 Muslims, including personal information such as bank account statements, passport details and records of their movements. The leak also showed that police had at times planted cameras inside mosques and used undercover agents to infiltrate Islamic nonprofit organizations and halal grocers and restaurants.

“Police agents were stationed undercover in mosques all over the country, and the surveillance program extended to almost every other center of Muslim life, from halal shops to what the police bizarrely deemed “Islam-related” organizations that included Doctors Without Borders, UNESCO, and other prominent NGOs,” said Igeta Daisuke, one of the plaintiff attorneys involved in the case.