Deep floodwaters and the risk of more mudslides that left about 20 people confirmed or presumed dead hampered search and rescue operations on Sunday in southern Japan, including at elderly home facilities where more than a dozen perished and scores are still stranded.

Rescue helicopters plucked more people from their homes in the Kumamoto region. Up to 10,000 defense troops, the coast guard and fire brigades are taking part in the operation.

Large areas along the Kuma River were swallowed by floodwaters with many houses, buildings and vehicles submerged almost up to their roofs. Mudslides smashed into houses, sending people atop rooftops waiving at rescuers.

At a flooded elderly care home in Kuma Village, 14 residents were presumed dead after rescuers reached them on Saturday, officials said. Three others had hypothermia.

The rescue continued Sunday for dozens of other residents and caregivers who were still at the riverside care facility Senjuen, where about 60 people were trapped when floodwaters and mud gushed in, officials said.

In Hitoyoshi City, the deluge poured into houses near the main train station. “The water rose to the second floor so fast and I just couldn’t stop shivering,” a 55-year-old woman who was visiting her relatives told the Asahi newspaper.

She and her relatives ran upstairs, swam out of the window and eventually took refuge on the roof to wait for their rescue.

More than 75,000 residents in the prefectures of Kumamoto and Kagoshima were urged to evacuate following pounding rains on Friday evening and into Saturday. The evacuation was not mandatory and many people opted to stay home because of concerns over catching the coronavirus, even though officials say shelters are adequately equipped with partitions and other safety measures.

Flooding also cut off power and communication lines, further delaying the search and rescue. Nearly 6,000 homes in Kumamoto were still without electricity Sunday, according to the Kyushu Electric Power Co.

The rainfall that exceeded 100 millimeters (4 inches) per hour has since subsided but the Japan Meteorological Agency has kept mudslide warnings in place across Kumamoto.