Floods unleashed by torrential rains in eastern Kentucky have killed at least 28 people, including four children, Governor Andy Beshear said as authorities worked to provide food and shelter for thousands of displaced residents.

Some homes in the hardest hit areas were swept away after days of heavy rainfall that Beshear has described as some of the worst in the U.S. state’s history. Rescue teams guided motor boats through residential and commercial areas searching for victims.

Officials warn the death toll may continue to rise with more expected rainfall potentially hampering rescue efforts. The National Weather Service forecasts several rounds of showers and storms through Tuesday, with a flood watch in effect through Monday morning in southern and eastern Kentucky.