LITTLE ROCK - A "catastrophic" tornado tore through the southern US state of Arkansas on Friday, and authorities said it caused "widespread damage" and left 24 people hospitalised.
One witness, Lara Farrar, told AFP that damage in West Little Rock was "shocking" with roofs torn off buildings.
No immediate fatalities were reported.
Governor Sarah Huckabee Sanders wrote that she had activated the National Guard to assist emergency services working to "assist anyone injured."
"Significant damage has occurred in Central Arkansas," Sanders wrote.
The National Weather Service issued tornado warnings for parts of the nearby states of Tennessee, Illinois and Iowa.
It said the tornado that steamrolled over parts of Little Rock was "catastrophic" in its force.
"This was actually an incredibly devastating tornado," Farrar told AFP.
She said she drove to West Little Rock and got out of her car at a blocked intersection.
"I was basically in total shock because the neighborhood had been basically completely wiped out and destroyed," Farrar said.
"Some of the buildings had the roof completely blown off."
She said the path of the tornado was about half a kilometre, leaving intense destruction, but outside the direct path damage was "very minor."
The mayor of Little Rock, Frank Scott Jr., tweeted that "we know of 24 people who have been hospitalised" in the area.
"Property damage is extensive and we are still responding."
Authorities in Pulaski County surrounding the state capital said it suffered "significant storm and tornado damage."
More than 78,000 people were without power across the state, according to Poweroutage.us.
The governor's office could not immediately confirm any casualties to AFP, but a local hospital told the Arkansas Democrat-Gazette that it had already begun to receive patients, including "a few" in critical condition.
Tornadoes are common in the United States, especially in the center and south of the country.
A week ago, a tornado swept through Rolling Fork, a small town in Mississippi, killing 13 people and causing extensive property damage.