Several thousand Japanese protesters have gathered at various locations in Tokyo to denounce the restart of nuclear reactors.
The Ohi plant in western Japan is the only one in the country up and running again, following the shutdown brought about by the disaster at Fukushima in the aftermath of last year's earthquake and tsunami.
Protests took place outside parliament and the prime minister's office.
"I am worried not only for her children, but for future generations," said one protester holding a child. "Japan doesn't need nuclear power plants."
"I want my kids to learn from me and my wife, and to become adults who can fight for their own rights," said another.
Japan's nuclear regulatory body is divided over the Ohi plant's renewed operation.
One geologist believes it sits on a potentially dangerous seismic fault. Others say more research is needed.