September 11th through 19th is a national week of action against nuclear power, and there are many demonstrations and other events have been organized throughout Japan.
See this blog for more detail.
On September 11th, thousands of people marched on the street of Tokyo. However, many demonstrators complained about the police trying to disturb the protest. Take a look at pictures taken by a photojournalist Munesuke Yamamoto HERE.
In the Shinjuku demo, 12 protesters were arrested. Seven of them have been released, but the rest is still being detained.
On the 19th, which is a national holiday in Japan, the “Goodbye to Nuclear Power Plants” rally will be held at Meiji Park in Tokyo.