Tornadoes have hit several US states, with “multiple fatalities” expected in Kentucky, where several buildings have collapsed.
The state’s Governor Andy Beshear said Kentucky had “experienced some of the worst tornado damage we’ve seen in a long time”.
In the community of Mayfield many buildings collapsed, with several people reported stuck inside a damaged candle factory.
“We expect multiple fatalities”, Mr Beshear said.
Elsewhere, at least five people were confirmed to have died, and emergency crews in Illinois are responding to reports of injuries at an Amazon warehouse after the roof collapsed.
Three people died in Tennessee, while one person died and several were injured when an apparent tornado hit a nursing home in Arkansas, and at least one fatality has been reported in Missouri.
Footage from local TV stations showed dozens of emergency vehicles at the Amazon centre near Edwardsville, about 25 miles west of St Louis.
Some 100 employees were believed to have been working the night shift at the time of the collapse, an official told local TV station KTVI-TV.
It was not immediately clear if or how many people were hurt, but the Collinsville, Illinois, Emergency Management Agency called it a “mass casualty incident” on Facebook.
Amazon spokesperson Richard Rocha said in a statement that the company was assessing the situation.
He said: “The safety and well-being of our employees and partners is our top priority right now.”
Illinois Governor J.B. Pritzker also tweeted: “My prayers are with the people of Edwardsville tonight, and I’ve reached out to the mayor to provide any needed state resources.”
It has not yet been confirmed if there are any injuries, but one person was flown by helicopter to a hospital.
Edwardsville Police Chief Mike Fillback said several people who were in the building were taken by bus to the police station in nearby Pontoon Beach for evaluation.
The Amazon centre opened with two warehouses in 2016, with 1.5 million sq ft of space, according to the Belleville News-Democrat.
The warehouses are used to store items, before then being shipped to mail-order customers.
It comes after severe weather – including a thunderstorm and a tornado – ripped through the wider St Louis area.
Winds of up to 70mph were reported in parts of the counties of St Charles and St Louis in Missouri.
At least three St Charles County residents were taken to hospital and several homes in the area near Augusta were damaged.
Further storms were reported in Arkansas, with several places in the Midwest also reporting tornados.
At least one person died died after a reported tornado ripped through a nursing home in Arkansas.
And in Tennessee, two storm-related fatalities were reported in Obion County in the state’s northwestern corner, said Dean Flener, spokesman for the Tennessee Emergency Management Agency.
He added that he had no details on the deaths.
Craighead County judge Marvin Day told The Associated Press that a tornado struck the Monette Manor nursing home in Arkansas at about 8.15pm, trapping 20 people inside as the building collapsed.
Five people had serious injuries, and a few others had minor ones, he said.
“It looks like it’s pretty much destroyed,” Mr Day said of the building.
“It happens quick but apparently there was a little bit of time with tornado sirens going off.”
Some residents were found in the basement “and were prepared for this”, he added.
The storms caused additional damage as they moved through Tennessee and into Kentucky.