Rescue workers carried out house-to-house searches in the increasingly unlikely hope of finding survivors after days of deadly floods and landslides that have claimed 179 lives in Japan's worst weather-related disaster for decades, Gulf News reported.

The record downpours that began last week have stopped and receding flood waters have laid bare the destruction that has cut a swathe through the west of the country.

In the city of Kurashiki, the flooding engulfed entire districts at one point, forcing some people to their rooftops to wait for rescue, reports Gulf News.

By Tuesday morning, rescue workers were going door-to-door, looking for survivors – or victims – of the disaster.

"It's what we call a grid operation, where we are checking every single house to see if there are people still trapped inside them," an official with the local Okayama prefecture government told AFP.

"We know it's a race against time, we are trying as hard as we can."

Hideto Yamanaka was leading a team of around 60 firefighters dispatched from outside the prefecture searching homes, Gulf News reported.

"I'm afraid elderly people who were living alone may have failed to escape," said Yamanaka, 53.