Ahead of this week's trip to Geneva to address the United Nations Human Rights Council about perceived Japanese government abuses, Hiroji Yamashiro, chairman of the Okinawa Peace Action Center, has described himself as a "prisoner of conscience."

In an interview in the city of Okinawa, Yamashiro said his prolonged detention from last October to March this year was an attempt by Tokyo to stifle free speech and Okinawans' protests against the construction of new military facilities on their islands.

Yamashiro had been detained on rolling charges of cutting barbed wire and shaking the arm of a public official at the construction site of new U.S. Marine Corps Osprey pads in Takae, and the piling of concrete blocks to obstruct access to another new installation at Henoko.