The Meteorological Agency on Saturday issued its highest-level alert as "unprecedented" torrential rains hit parts of Ishikawa Prefecture that were rocked by the New Year's Day earthquake, flooding rivers, triggering mudslides and leaving at least one dead and several others missing.

The cities of Wajima and Suzu, as well as the town of Noto — which are still recovering from the powerful quake earlier this year — were being hit particularly hard by the rains, with many buildings and roads inundated and the agency warning of the possibility of further flooding and landslides in the coming hours.

One person had been confirmed dead in a landslide and another missing in Suzu, while one person from Wajima and another from Noto were also missing as of 4 p.m., the Ishikawa Prefectural Government said. Two others were seriously injured.