An exceptional number of powerful tornadoes have ravaged parts of Oklahoma and nearby Great Plains states, with one small town reportedly hit by two separate tornadoes within hours, authorities said Sunday.

After 78 tornadoes were reported Friday, mostly in Nebraska and Iowa, a separate weather system Saturday brought 35 tornado reports from northern Texas to Missouri, the National Weather Service said.

At least four people, including a four-month-old child, died in the Oklahoma town of Holdenville, according to multiple reports in state and local media, though crews on Sunday were still sifting through the mounds of rubble.

The storms dumped up to seven inches (18 centimetres) of rain in some places within hours, and meteorologists warned of a continuing danger of extreme weather Sunday, including flash flooding, hail and more tornadoes.

Videos and images posted on social media showed scores of buildings flattened in the small town of Sulphur, in south-central Oklahoma, with vehicles smashed or overturned and trees stripped of branches and leaves.

Postal trucks in Sulphur rested precariously atop the nearly unrecognizable wreckage of buildings, one video showed. Rescue crews went house to house and vehicle to vehicle in search of victims or survivors.

“DO NOT COME TO SULPHUR UNLESS YOU ARE A FIRST RESPONDER!!!” the Murray County sheriff’s office said in a Facebook post.

A tornado that struck Ardmore, Oklahoma tossed debris up to 20,000 feet (6,100 meters) high, the Washington Post reported. Then two other tornadoes came close to the town in the ensuing two hours.

Oklahoma Governor Kevin Stitt declared a 30-day state of emergency to expedite aid to 12 of the hardest-hit counties.

More than 50,000 homes in Texas and more than 30,000 in Oklahoma were without power as of late Sunday morning, the poweroutage.us website reported.

The region is known for the frequency and power of the tornadoes that rumble through every spring. But having separate major outbreaks in succeeding days is exceedingly rare, meteorologists said. (AFP)

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