A wrecked vehicle lies among the debris at the boy scout camp in Little Sioux, Iowa, on Thursday, when a tornado killed four youths. (Office of the Gov. of Nebraska/Associated Press)

Dozens of teenage boy scouts caught in a deadly tornado in Iowa immediately put their life-saving skills to use Wednesday night, pulling their friends and leaders out from heaps of rubble, officials said.

The tornado, which struck an isolated boy scout camp about an hour north of Omaha, Neb., killed four of the boys — three 13-year-olds and one 14-year-old. Another 48 people were injured.

"There are some real heroes at the scout camp," Iowa Gov. Chet Culver said at a press conference Thursday in the town of Blencoe.

"After the tornado hit directly on their bunkhouse, they immediately started helping each other in this time of need."

Rob Logsdon, a 15-year-old boy scout, said there was almost no warning when the storm hit the Little Sioux Scout Ranch at about 6:30 p.m. CT. He said they saw it coming over a bluff, and about seven or eight minutes later it hit.

The scouts at the site — about 90 regular scouts and 25 leaders — were spread out across the camp at the time. Logsdon and his group ducked under tables in a small camp building.

The remains of a ranger's house at the Little Sioux Scout Ranch can be seen after a tornado ripped through it in the remote Loess Hills, Iowa, on Wednesday. (Loren Sawyer/Onawa Sentinel/Associated Press)

"Two seconds after, the tornado hit, the doors ripped open, my ears popped pretty bad and then all of a sudden there was this gust of wind, and the next thing I know, all the walls and the roof were gone off the shelter," he told CBC News on Thursday morning.

He said a chimney fell over and crushed his good friend, killing him. "I saw him laying there, he wasn't moving," Logsdon said.

Logsdon said that during the storm a table hit him in the back and a chair hit him in the face, and he was thrown to the ground. He frantically tried to free a friend who was trapped under a pile of bricks, but had to stop when his hip popped and he could no longer stand up straight.

Other boys set up triage stations, worked chainsaws to clear debris, and carried their injured friends to ambulances and helicopters.

Speaking at a news conference on Thursday afternoon, U.S. Secretary of Homeland Security Michael Chertoff offered condolences on behalf of President George W. Bush to those who lost loved ones, not just at the boy scout camp, but in floods across the region over the past several days.

"It seems like the boy scouts didn't have a chance because it came so fast and so hard," Chertoff said.

"I could see a pickup truck just kind of flung like a child's toy. So it's truly a tragic act of God. Looking at the trees mowed down, it's not hard to understand the impact of this kind of tornado."

Tornado drill a day earlier

Chertoff, as well as scout officials, praised the boys' efforts following the storm.

"[The scouts] were out there practising first aid, saving their friends, saving other scouts, saving the life of our camp director, who was under a house," Lloyd Roitstein, executive director of the Boy Scouts of America’s Mid-American Council, said Thursday in Omaha.

An unidentified boy scout leaves the West Harrison High School in Mondamin, Iowa, on Thursday after being reunited with relatives. (Nati Harnik/Associated Press)

At one point, many of the scouts who survived gathered outside at their leader's badly damaged car, which was thrown about 50 metres and left with a missing wheel and a dented roof. The boys prayed together and tried to calm each other down.

"There were a couple of kids that were really scared and stressed out and a couple of them were sobbing uncontrollably," said Logsdon, who said he is still sore from his injuries.

Roitstein said the boys had just done a tornado drill the day before the storm. The group of scouts at the camp — from Iowa, Nebraska and South Dakota — were invited to attend the 730-hectares camp for a week after being chosen as future leaders.

They were being trained in leadership skills and were supposed to take those skills back to their own troops.

Of the 48 injured scouts, 42 were sent to hospital, said Jim Saunders of Iowa's public safety department.

"Some of those injuries are significant, but I'm being told there's nothing to indicate they are life-threatening," he told CBC News on Thursday morning.

Kansas tornado ravages small town

A line of tornadoes also raked Kansas on Wednesday, killing at least two people and destroying much of the small town of Chapman, north of Wichita, in Dickinson County.

About 100 homes in the town were destroyed by the 10:30 p.m. storms, said Brad Homman, director of administration and emergency services in the county.

"We have no electricity or water or gas at this point," Hammon said. "It may be days before it's restored."

One victim was found in a Chapman yard, while the other was found outside a mobile home in the nearby Jackson County town of Soldier, said state official Sharon Watson.

With files from the Associated Press