Eight children from a home for neglected and abused youths have been killed in a crash involving 18 vehicles on an Alabama highway.
A 29-year-old father and his nine-month-old girl who were in another vehicle were also killed, said Butler County Coroner Wayne Garlock, who confirmed the 10 deaths on Monday morning (Australian time).
The crash occurred as tropical depression Claudette swept across the south-eastern US, causing flash flooding and spurring tornadoes that destroyed dozens of homes.
Butler County sheriff Danny Bond told the Montgomery Advertiser that the crash was “the worst traffic accident I’ve witnessed in my life”.
The eight foster children, aged four to 17, were returning from a tip to the beach when their van burst into flames after colliding with the car carrying the dad and baby.
That was followed by a pile-up of about 18 vehicles on a downhill stretch leading to a bridge over a creek, Mr Bond said.
Five others were hurt but none were critical, he said.
Alabama Law Enforcement Agency officials are investigating whether the accident could have been caused by vehicles hydroplaning on the wet road, he said.
Michael Smith, chief executive of the Tallapoosa Ranch, which housed four of the dead girls, told Reuters: “It was horrendous.”
“I’ve never seen anything like it in my whole life,” he said.
A 24-year-old man and a three-year-old boy had earlier been killed when a tree fell on their house just outside the Tuscaloosa city limits.
Rains pelted much of northern Alabama and Georgia late on Saturday (local time). As much as 30 centimetres of rain was reported earlier from Claudette along the Mississippi Gulf Coast.
National Hurricane Centre forecasters predicted that by Monday Claudette would strengthen back to tropical storm status over eastern North Carolina as it went out to sea in the Atlantic Ocean.
More than 20 people were rescued by boat due to flooding in Northport, Alabama, WVUA-TV reported.
Claudette was named a tropical storm early on Saturday, well after its centre of circulation made landfall south-west of New Orleans.
Shortly after, a suspected tornado spurred by the storm demolished or badly damaged at least 50 homes in a small town in Alabama, just north of the Florida border.
Sheriff Heath Jackson in Escambia County said a suspected tornado “pretty much levelled” a mobile home park, toppled trees onto houses and ripped the roof off of a high school gym.
Most of the damage was done in or near the towns of Brewton and East Brewton, about 77 kilometres north of Pensacola, Florida.
“It kind of affected everybody,” Mr Jackson said.
“But with those mobile homes being built so close together it can take a toll on them a lot more than it can on houses that are spread apart.”
Tornadoes were also reported in south-west Georgia.