Search and rescue operations continue on Aug. 14 and 15 at the site of a landslide triggered by heavy rain in Unzen, Nagasaki Prefecture. (Provided by the Unzen city government)

At least four people have died and five are still unaccounted for following record-breaking rainfall that had continued to pound western and eastern Japan since Aug. 11.

The Japan Meteorological Agency is calling on residents to remain on the alert against more flooding and landslides as the same rain front that brought downpours is expected to again approach the Japanese archipelago and linger until around Aug. 20.

A landslide on Aug. 15 caused by torrential rains slammed into a house on a mountain slope in Okaya, Nagano Prefecture, killing Yuki Makibuchi, 41, and her second and third sons, 12 and 7, all of whom were in the home at the time.

Fumiyo Mori, 59, also died in a rain-triggered landslide in the early hours of Aug. 13 in Unzen, Nagasaki Prefecture. Her husband, 67, and their daughter, 32, remain unaccounted for.

Officials found three other bodies and are investigating whether the deaths are also related to heavy rainfall.

Of the five people listed as missing, two went missing in Hiroshima Prefecture, two in Nagasaki Prefecture and one in Kumamoto Prefecture.

Heavy rainfall had caused 44 landslides in 15 prefectures, mainly in western Japan, as of noon on Aug. 15, according to the land ministry.

As of 8:40 a.m. on Aug. 16, the second highest level 4 warning had been issued for residents in Nagano, Fukuoka and Saga prefectures to urge them to be vigilant against landslides.