Three journalists who worked on the Panama Papers have been describing their work on the data, a massive leak that revealed the offshore holdings of politicians, business leaders and celebrities worldwide.

Freelancer Scilla Alecci, Asahi Shimbun reporter Toshihiro Okuyama and Kyodo News reporter Yasuomi Sawa attended a symposium at Tokyo's Waseda University in early June. The leak was first reported in April and has led to the resignations of a number of public officials.

"Although the names and addresses of subjects under investigation have been released to the public online, we are the only people in Japan with direct access to the Panama Papers themselves," Okuyama said. He added, this gives them a "moral obligation" to share the findings with the public.