TOKYO - Japan's disaster management agency said the death toll from recent flooding has risen to 50 and at least a dozen others are still missing.

Pounding rain since late Friday in Japan's southern region of Kyushu has triggered widespread flooding.

The Fire and Disaster Management Agency said 49 of the dead confirmed as of Tuesday morning were from riverside towns in the Kumamoto prefecture. One person was found dead in another prefecture of Fukuoka as the heavy rain spread across the southern area. At least a dozen people are missing.

Tens of thousands of army troops, police and other rescue workers mobilized from around the country worked their way through mud and debris in the hardest-hit riverside towns along the Kuma River.

Rescue operations have been hampered by the floodwater and continuing harsh weather that have caused more flooding elsewhere in the Kyushu region including Fukuoka and Oita.

In the Omuta district of Fukuoka, residents were being rescued on boats by defence troops. A 2-month old baby was among them.

An elderly woman who was also evacuated told NHK television that she started walking down the road to evacuate, but floodwater rose quickly up to her neck. “I was almost washed away and had to grab a electrical pole.”

About 3 million residents were advised to evacuate across the Kyushu region.

Among the victims were 14 of the 65 elderly residents of a nursing home next to the Kuma River, known as the “raging river” because it is joined by another river just upstream and is prone to flooding. The river rose abruptly and its embankment gave in, causing floodwater to gush into the nursing home Senjuen. Most of the residents were bedridden or wheelchair users. There was no elevator at the facility.

U.N. Secretary-General Antonio Guterres was “deeply saddened” by the deaths and “expressed his deep condolences to the families of the victims, as well as to the people and government of Japan,” U.N. spokesman Stephane Dujarric said.