Four killed as tornado flattens US Scout camp

A boy Scout is wheeled out of the West Harrison High School in Mondamin, Iowa, early Thursday morning. (AP)

A tornado tore through a Scout camp in Iowa on Wednesday, killing four people and injuring at least 40 in the midwestern US state, a scout official said.

Lloyd Roitstein, president of the Boy Scouts of Mid-America Council, told CNN television that the Little Sioux Scout Ranch was "virtually destroyed" after the twister ripped tents off the ground, snapped trees and reduced buildings to rubble at the 1,800-acre (730-hectare) compound in Iowa's remote western hills.

"There's nothing left in there," Roitstein told the news network. "There are four confirmed dead, numerous injured."

The boys at the camp were between 13 and 18 years old and were there for a week of training, he said.

About 120 people, including 93 children, were at the camp when it was struck, CNN said, citing Iowa Public Safety Commissioner Gene Meyer.

It was not immediately clear if those killed were teens or adults.

At least 40 people were injured in the evening storm and were taken to area hospitals, Iowa Homeland Security spokeswoman Julie Tack said according to NBC News.

Many of the injured reportedly had been on a hike when the tornado struck, leaving them exposed to the deadly winds.

Tornadoes also touched down on Wednesday in the states of Minnesota and Nebraska, according to officials quoted by local media.

Late last month a tornado left seven people dead in north-central Iowa, while tornadoes on May 10 killed 22 people in Missouri, Oklahoma and Georgia.