At least one person died as severe weather erupted across a vast stretch of the United States on Sunday amid warnings of widespread damaging winds, tornadoes and hail as large as baseballs.

A tree fell on a travel trailer that was camped along the Illinois River between Tahlequah and Kansas, Okla., during heavy winds early on Sunday morning, trapping a couple inside, said Sheriff Jason Chennault of Cherokee County.

The man was pronounced dead at the scene, and the woman suffered minor injuries, Sheriff Chennault said.

The highest risk on Sunday covered a large area from northeastern Texas and northern Louisiana through Mississippi, northwestern Alabama, Illinois, Indiana, Ohio and southern Michigan, potentially affecting a population of more than 40 million people.

The Storm Prediction Center placed these areas under an enhanced risk level of three out of five on the severe weather scale.

Tornado watches popped up across Arkansas, Illinois, Indiana, Kentucky, Missouri and Tennessee on Sunday afternoon, according to the National Weather Service.

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