At least three people are missing after unprecedented rainfall Saturday in Noto, Kyodo News reported.

The region in Ishikawa Prefecture was hit hard by an earthquake with a magnitude of 7.6 on New Year's Day, prompting Japan's weather agency to issue an emergency heavy rain warning for the area.

More than 120 millimetres per hour of rainfall was recorded in the morning in Wajima the Noto region in the central Japan prefecture, as linear rainbands, known to bring torrential downpours, formed. It was the heaviest rain experienced in the area since records began.

Prefectural authorities said three people are missing after being swept away by rivers in Suzu, Wajima and Noto, the three municipalities where the warning was issued.

The Japan Meteorological Agency also warned that atmospheric conditions would become extremely unstable in the northeastern region of Tohoku due to the flow of warm, humid air into a low-pressure system.