At least one driver was swept away in flooding rains in Kentucky on Saturday as heavy rains prompted evacuations and a declaration of a state of emergency, the governor said.

“We’ve sadly already received reports of fatalities that we are working to confirm, and we need everyone to stay alert and do what’s needed to keep each other safe,” the governor, Andy Beshear, said on social media.

Governor Beshear said that Madison County was hit hard, with the floodwaters leaving many of its roads submerged.

He said, “We think we have multiple fatalities in that county.”

At least one motorist was swept away in flash flooding though it was not clear where that happened, the governor said. Five search-and-rescue teams have been sent to help residents, he added.

The governor said he had declared a state of emergency to make more resources available.

Forecasters expect as much as seven inches of rain on Saturday, he added. He said a second round of heavy rains could come this afternoon and up to 11 p.m.

Mr. Beshear urged residents to stay off the roads after dark, as emergency crews rescued people from flooded homes and vehicles.

Bullitt, Madison, Meade, Mercer and Spencer Counties declared local states of emergency, the governor said.

He said Bullitt County has “gotten hit hard” and faces a dam failure, with residents in part of that county being evacuated. Additional details were not immediately available.

This is a developing story. Check back for updates.