Freelance journalist Ryuichi Kino started attending press briefings at Tokyo Electric Power Co. shortly after the nuclear crisis erupted at its Fukushima No. 1 complex in March 2011, knowing that it was an event of world significance.

"I knew I would regret it if I missed covering an incident like this making world history," he said.

It was not long, though, before he began to suspect the utility was not coming clean, a view shared by an old friend he bumped into at the briefings, Kazuo Hizumi, who operated an online news site while working as a lawyer.