(Reuters) - Kentucky governor Andy Beshear declared a state emergency early on Monday after tornado-spawning thunderstorms swept the U.S. Southern Plains and Ozarks, killing at least 14 people and wrecking hundreds of buildings as forecasters warned of more severe weather.

"Severe weather continues to move through the commonwealth with multiple reports of wind damage and tornadoes," Beshear said in a post on X.

At least seven people perished and nearly 100 were injured on Saturday night when a powerful tornado struck communities in north Texas near the Oklahoma border, Governor Greg Abbott said at a news conference the next day.

On Sunday, as storms shifted to the northeast, unleashing more extreme weather across the U.S. heartland, a landscaper was killed by a tree toppled in winds that gusted to 80 miles per hour in Louisville, Kentucky, police said.

The Weather Service warned of additional storms moving through the Ohio and Tennessee valleys, bringing a mix of damaging winds, large hail and more tornadoes, as well as heavy downpours capable of triggering flash floods.

The latest bout of extreme weather came just days after a powerful tornado ripped through a rural Iowa town, killing four people, and more twisters touched down in Texas last week.

(Reporting by Surbhi Misra in Bengaluru; Editing by Mark Potter)