At least 14 dead from storms in Texas, Arkansas, Oklahoma and Kentucky

Search teams in the U.S. Southern Plains and Ozarks are assessing damage after tornado-spawning thunderstorms killed at least 14 people and destroyed hundreds of buildings. North Texas, near the Oklahoma border, was hit hardest, with seven fatalities and nearly 100 injuries. Severe weather delayed the Indianapolis 500. Tornadoes, with winds up to 135 mph, wreaked havoc, especially in Valley View, Texas, and other regions. As cleanup continues, forecasters warn of more storms, extreme heat, and a potentially severe Atlantic hurricane season starting June 1.