protest - Who has been demonstrating in Shanghai?

Just received some details from a confidential police report on last Saturday's anti-Japanese demonstration. They come from a rather reliable source, but I have not seen the material myself so should be treated with some caution.
According the the report the number of demonstrators has been around 20,000, half of whom were police officers. Yes, indeed: 10,000 police officers. I could recognize larger number of plain clothes police men, but would have never come to that number.
According to the report "no major accidents or disturbances" took place. That now might be an assessment that is not shared by the owners of the establishments that were demolished. Fifty people have been arrested for damaging property or stealing. The demonstrations have not been organized by any organization, the report says. I conclude then, that since nobody applied for an approval, the demonstration was not approved.
Next time, when all the police men stay at home, it might be a minor disturbance.

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