A criminal investigation now seems likely in the STAP stem-cell research debacle after a former Riken researcher filed a criminal complaint against disgraced scientist Haruko Obokata, alleging she stole samples of embryonic stem cells before reporting that she had created her version of stem cells with a novel technique.

Toshihisa Ishikawa, a former senior researcher at the government-affiliated scientific research organization, submitted the complaint to police in Hyogo Prefecture, where Obokata as a Riken researcher conducted her stem-cell research.

The work secured publication in the prestigious science journal Nature and was widely hailed as groundbreaking before allegations of fabrication emerged.