Japanese authorities told tens of thousands of people to evacuate the quake-hit region of Ishikawa on Saturday as “unprecedented” rains triggered floods and landslides.
A dozen rivers in the region, on the west coast of central Japan, had burst their banks by 11:00 am (0200 GMT), land ministry official Masaru Kojima said.
Three people were missing in Ishikawa, public broadcaster NHK reported, two of them carried away by strong river currents.
At least one person was missing further north in Wajima, and rescue workers were trying to confirm a report of another person missing, a local official told AFP.
Many buildings were inundated, with landslides blocking some roadways, the Ishikawa government said in a statement.
The cities of Wajima and Suzu, as well as Noto town, ordered about 44,700 residents to evacuate, officials said.
The Japan Meteorological Agency (JMA) said it issued its highest-level warning for Ishikawa, cautioning of a “life-threatening situation”.
The areas under the warning were seeing “heavy rain of unprecedented levels”, JMA forecaster Satoshi Sugimoto told reporters, adding “it is a situation in which you have to secure your safety immediately”.
More than 120 millimetres (4.7 inches) of rainfall per hour was recorded in Wajima in the morning, the heaviest rain since comparative data became available in 1929.
Footage on NHK showed an entire street submerged in Wajima.
Prime Minister Fumio Kishida instructed the government “to do its best in disaster management with saving people’s lives as the first priority”, top government spokesman Yoshimasa Hayashi told reporters.