At least one person has died after a large tornado tore through New Orleans, destroying homes and taking out power.
Videos showed the dark funnel cloud ploughing through neighbourhoods on Tuesday night, blowing off rooftops and overturning cars.
It hit suburbs that were devastated by Hurricane Katrina in 2005.
The tornado was spawned by a storm system which caused widespread damage and killed a woman in Texas and Oklahoma on Monday.
Officials in the eastern St Bernard district said rescuers were searching for people who may be trapped after one person was killed and several injured.
Its parish president Guy McInnis said several houses there had been “totally demolished”.
Photos from the St Bernard neighbourhood of Arabi show crumpled cars, collapsed buildings and debris scattered across streets.
“There are houses that are missing,” local sheriff James Pohlmann told The New York Times. “One landed in the middle of the street, and there was somebody trapped in that house.”
One resident, Reggie Ford, posted a video showing wrecked buildings.
He told told the news agency Associated Press: “I see downed powerlines. A church is completely destroyed. Three businesses are completely destroyed. There are eight blocks of houses missing their roofs.”
The trapped person was reportedly later rescued and taken to hospital.
Louisiana Governor John Bel Edwards said authorities were assessing the storm’s impact.
“My prayers are with you in Southeast Louisiana tonight. Please be safe,” he tweeted.
The tornado was produced by a storm front working its way across southern US states on Tuesday, bringing heavy rain and powerful winds to Louisiana, Mississippi and Alabama.
An elderly woman was killed about 60 miles (96km) north of Dallas when a tornado struck the area on Monday.
“A damaging gust or a tornado remains possible over the next few hours,” the US National Weather Service tweeted.