At least three people have died in flash floods caused by heavy rain and multiple thunderstorms in Kentucky, officials said, with additional fatalities expected to be confirmed soon.

The severe weather event promoted Gov. Andy Beshear to declare a state of emergency Saturday. Beshear warned Kentucky residents in a video message not to drive after dark, adding that a motorist was swept away and killed by the floods.

“We know we’ve already lost at least a handful of Kentuckians. I don’t want to lose any more. Be safe, everyone,” he said.

In Madison County, three adults died in the flooding, county Coroner Jimmy Cornelison said. Their identities and additional details have not been publicly released. It was not immediately clear whether the motorist was among the three.

Beshear said one fatality was also suspected in Jackson County.

Beshear said the storms were more severe than expected, bringing six to seven inches of rain in some parts of the state. Heavy rainfall is expected to let up by 11 p.m. local time, but officials remain concerned about waterlogged roads and downed trees and debris. Many counties remain under a flood watch through Saturday night, according to the National Weather Service.

Five counties — Bullitt, Madison, Meade, Mercer and Spencer — have declared local states of emergency.

Emergency responders were assisting with rescue operations Saturday, including water rescues from vehicles and homes.

Five search and rescue teams have been sent to the Madison County area, Beshear said, and high-axle vehicles are being used to assist with water rescues. An emergency landing station has opened for flood victims at a local shelter, Madison Home.

After reporting a “moderate dam failure” on Saturday, Bullitt County issued an urgent evacuation notice for some residents in Lebanon Junction, advising them to move to higher ground. Hours later, the county reported on Facebook that “flood waters may be starting to recede in some areas, but the danger is not over.”

Any area can be vulnerable to flash floods, which can occur within minutes to hours of heavy rainfall, swallowing roads and creating dangerous currents in rivers and creeks. Heavier rainfall driven by climate change has contributed to more frequent and severe flooding in many parts of the U.S.

Catastrophic floods in the Texas Hill County last year killed 139 people, including 25 girls, two teenage counselors and the director at a Christian summer camp. The floods began in the early morning hours of July 4, while many people were still asleep in their homes and visitors were camped along the Guadalupe River in anticipation of the Fourth of July. The river surged to unprecedented heights in less than an hour, carrying homes and vehicles for miles downstream.