At least 14 people reportedly died and hundreds of buildings were wrecked even as search teams picked through wreckage left by tornado-spawning thunderstorms that swept the US Southern Plains and Ozarks on Saturday-Sunday.

Forecasters warned of more severe weather over the holiday weekend.

In Indiana, storms delayed Sunday’s scheduled start of the Indianapolis 500-Mile Race, or Indy 500, the premier US auto racing event traditionally held over the Memorial Day weekend.

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, reported Reuters.

He said two children, aged 2 and 5 from a single family, were among the dead in and around the tiny Cooke County town of Valley View, which bore the brunt of the twister.

More than 200 homes and other structures were listed as destroyed, with another 120 buildings damaged in a zone that stretched over 50 miles, Abbott said.

A National Weather Service official said the Valley View tornado packed top winds of 135 miles per hour.

Multiple twisters hit the region, but the precise number had yet to be determined, she said.

As the scale of the disaster came into fuller view on Sunday, officials were wrapping up initial search-and-rescue operations, the governor said.

He said authorities would make one final sweep of damaged buildings for possible additional victims but that nobody else was reported missing by day’s end.

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.

As Texas residents struggled to regain their footing from a night of thunderstorms and tornadoes, excessive heat warnings and heat advisories were posted on Sunday across the southern tier of the state and along the Gulf Coast into most of Louisiana.

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.

Meanwhile, the US was preparing for what government forecasters have called a potentially “extraordinary” 2024 Atlantic hurricane season beginning June 1.