Tornadoes have ripped through the US state of Texas, killing at least four people and injuring dozens of others.

Key points: Three tornadoes were confirmed in Texas, storms and flooding in neighbouring states

Three tornadoes were confirmed in Texas, storms and flooding in neighbouring states Four people have been killed and 49 others injured by tornadoes

Four people have been killed and 49 others injured by tornadoes Another five were killed in storms and flooding

Severe storms in neighbouring states also left five people dead, including three people killed by flooding and winds in Arkansas, with officials saying two more people are missing.

Rushing water swept away a car, drowning a woman in Missouri, and two deaths were reported in Mississippi.

In total, at least 14 people have been killed by tornadoes or flooding in the country's south and midwest.

In Texas, three tornadoes were confirmed by the US National Weather Service in Canton, a city about 95 kilometres east of Dallas.

The tornado flattened a barn in Canton, Texas. ( Reuters: Brandon Wade )

Winds flipped cars, snapped trees, destroyed houses, and left roads strewn with debris and fallen power lines.

Kris Ingram looks for his belongings in the ruins of a barn destroyed by a tornado. ( Reuters: Brandon Wade )

Greg Abbott, the Governor of Texas, said more than 5,000 addresses had been impacted by the tornadoes.

"We've heard some reports, yet unconfirmed, that there's a possibility that one of these tornadoes was on the ground for up to a 50-mile stretch, which would be the longest stretch of a tornado on the ground that I've ever heard of," he said.

Canton Mayor Lou Ann Everett said it was possible the number of dead could rise.

"The damage was extensive in the affected area. It is heartbreaking and upsetting," she said.

The tornado tore through a car dealership near Canton, Texas. ( AP: Tom Fox )

Forty-nine people had been treated for injuries, Ms Everett added.

The mayor urged people to stay away from a sprawling flea market known as First Monday Trade Days, as crews tried to clean up debris.

The Governor has also deployed a search and rescue team to the area.

Homeowners clean up debris after a tornado hit the town of Emory, Texas. ( Reuters: Brandon Wade )

Storms and flooding hit other states

The storms caused floods in neighbouring states, killing a 72-year-old woman in south-western Missouri who was washed away in her car, according to local media reports.

In Arkansas, a woman was killed when a tree fell on her mobile home in DeWitt, and a 10-year-old girl was killed after flood waters swept her away in Springdale.

A fire chief responding to the storm was killed on Sunday in Cleburne County, the county sheriff said.

Winds of up to 95 kilometres an hour tore trees out of the ground. ( AP: Sarah A. Miller )

In Mississippi, a person was killed after a tree fell on their house in Durant.

The governors of Missouri and Oklahoma declared states of emergency due to flooding.

Missouri Governor Eric Greitens said some people were told to evacuate and 33 rescues were conducted, mostly in the state's central and south-western regions.

Parts of Indiana received up to 203 millimetres of rain while areas in Oklahoma, Missouri and Arkansas were drenched with up to 101 millimetres.

A funnel cloud forming near Troy, Alabama. ( AP )

Reuters/AP