Iowa tornado kills seven people, including two children

Seven people were killed Saturday, including two children under the age of five, when a tornado swept through central Iowa, damaging buildings and knocking down trees and power lines, in the deadliest storm to hit the state since 2008, authorities said.

Emergency management officials in Madison county said four were injured in addition to those killed when the tornado touched down in the area south-west of state capital Des Moines at about 4.30pm. Among those killed were children and adults.

In Lucas county, officials confirmed one death and multiple reported injuries.

The state department of natural resources said that the person who died was in an RV at a campground at Red Haw State Park in Chariton, Iowa.

Iowa governor Kim Reynolds issued a disaster proclamation for the county, which allows state resources to be used to assist with response and recovery efforts.

Wendy Burkett told the Des Moines Register she and two of her three daughters were in their house Saturday afternoon when her husband, Tony, called her from a nearby shed where he was working and alerted her about a tornado warning.

They hurried with their daughters to their basement as the tornado roared by within seconds. As they clung to each other, a window shattered outwards and water began spewing from the pipes, she said.

But within about a minute, the tornado passed by, and while the family was unhurt, their home was in ruins amid debris all around, even in the trees.

The National Weather Service in Des Moines tweeted later Saturday that initial photos and videos from the damage around the community of Winterset suggested it was at least an EF-3 tornado, capable of causing severe damage, on the Enhanced Fujita scale.

It said weather service teams would investigate the damage Sunday and further assess a potential rating.

Thunderstorms that spawned tornadoes moved through much of Iowa from the afternoon until Saturday night with storms also causing damage in the Des Moines suburb of Norwalk, areas just east of Des Moines and other areas of eastern Iowa.

The storms are the deadliest to occur in Iowa since May 2008 when one tornado destroyed nearly 300 homes and killed nine people in the northern Iowa city of Parkersburg. Another tornado a month later in the state killed four boys.

Northern Illinois University meteorology professor Victor Gensini said there have been plenty of examples of deadly storms in March even though they are more common in April and May.

Scientists have said that extreme weather events and warmer temperatures are more likely to occur with human-caused climate change.

However, scientifically attributing a storm system to global warming requires specific analysis and computer simulations that take time.

Officials reported a number of homes were damaged, roads were blocked by downed lines and tree branches were shredded by the strong winds.

Power outages affected about 10,000 in the Des Moines area.