|The storm caused massive destruction across Mississippi, flattening homes and buildings [AFP]
At least 10 people have been killed in the southern US state of Mississippi after dozens of massive tornadoes struck the area.
Up to 30 tornadoes swept across the state beginning on Saturday, with the largest more than one kilometre wide packing winds that topped 260kph, weather experts said.
The severe weather began in Mississippi's neighbouring state of Louisiana, where a tornado destroyed 12 homes.
The storm system then moved east, hitting nearby Yazoo county in Mississippi, killing four people.
In adjacent Holmes county, another person was killed while to the northeast in Choctaw county tornadoes killed another five people, including children aged 3 months, nine and 14.
On Sunday as residents began to try to clear up after the storms Haley Barbour, the governor of Mississippi, declared a state of emergency in 17 counties describing the destruction as "utter obliteration".
"This tornado was enormous," he told the Associated Press.
Officials have deployed the US National Guard to the area, to protect damaged homes from the threat of looting.
Jay Gray, an NBC news reporter, told Al Jazeera that people who had left the area have come back to nothing but debris.
|The tornadoes left a trail of devastation and recovery may take years [AFP]
He said there was very little left of Yazoo City after a tornado swept through.
He said it appeared some of the buildings had been ripped inside out by the power of the storm.
"It stretches for miles and this storm has cut a widely and deadly path across this state," he said.
"Recovery is going to take months, and possibly years to really assess what's happened here. Residents are stunned right now, but are beginning to understand the reality and magnitude of the task ahead."
Paige Roberts, spokesperson for the American Red Cross, told Al Jazeera that emergency response vehicles have been going through the damaged neighbourhoods, and were delivering meals, snacks and water.
"They have also been bringing back critical information about the immediate needs of those affected. But you can imagine this task is very daunting for many people, and also quite heartbreaking," she said.
Tornadoes were also reported in Louisiana, Arkansas and Alabama.