Olympic silver medalist race walker Koki Ikeda of Japan has been provisionally banned for suspected blood doping, track and field’s Athletics Integrity Unit said on Friday.

Ikeda was second in the 20-kilometer event at the Tokyo Olympics in 2021 and placed seventh at the Paris Olympics three months ago.

The 26-year-old walker was notified of a charge based on suspect readings in his biological passport, the AIU said. The passport can indicate markers of doping over time without an athlete testing positive for a banned drug.

The investigators gave no timetable for the disciplinary case.

Ikeda also took silver at the 2022 world championships in Eugene, Oregon.