INA- SOURCES
The National Weather Service (NWS) said a preliminary investigation had confirmed some of Saturday's tornadoes had gusts of above 136 miles (218km) an hour.
The storms - which swept from Texas to Missouri - also saw up to seven inches (18cm) of rain fall in some places within hours, the AFP news agency reported.
The town of Sulphur, in eastern Oklahoma, was hit particularly hard. Video of the aftermath showed flattened homes and overturned vehicles.
According to the Oklahoma State Department of Health, around 100 injuries were reported.
The towns of Holdenville and Marietta were also badly damaged.
The speaker of the Oklahoma state House of Representatives, Charles McCall, insisted that the affected areas would recover.
"We will rise, we'll clean up, we'll rebuild and we'll move forward," he told a news conference in Sulphur on Sunday.
The state's Governor, Kevin Stitt, also visited the town and said the damage there was the worst he had seen in his six years in office.
"You just can't believe the destruction," he said.
"It seems like every business downtown has been destroyed."
The White House said US President Joe Biden had spoken with Mr Stitt and offered the federal government's full support.
It comes after a separate weather system brought more than 70 tornadoes to the Midwestern states of Nebraska and Iowa on Friday.
Most happened around the city of Omaha, where one resident described his ordeal.
"Saw this big tornado coming and just had to cover with the kids and wife as fast as we could," Brent Richardson told the Associated Press.
"Loudest freight train you've ever heard in your life coming right through your house."
"Utter destruction, just chaos. A neighbourhood that's trying to band together to help people out and you have some people trapped in houses that we're trying to get out and there's houses that aren't standing any more."
Nebraska's governor issued emergency declarations for three counties on Sunday, making them also eligible for extra funding towards rescue and recovery operations.
Further severe weather has been forecast.
"The threat of tornadoes appears to be lower, but instances of damaging winds and hail are still expected, especially across north-eastern Texas, northern Louisiana, Arkansas and southern Missouri," meteorologist Brandon Buckingham from the commercial forecaster AccuWeather reported.
SOURCE: BBC
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