A wave of tornadoes caused widespread damage and causalities in the south-central United States on Sunday, killing at least 18 people in Arkansas, Oklahoma and Iowa.

According to Reuters, Arkansas was the hardest hit with at least 16 people dead. At least 10 people died, including two children, in Arkansas' central Faulkner County, plus authorities said that at least 150 homes were destroyed in the most destructive storm system of the year.

"It was a devastating tornado," Arkansas Gov. Mike Beebe said at a news conference.

"What I'm seeing is something that I cannot describe in words," Faulkner County Sheriff Andy Shock said, reports NBC News. "It is utter and sheer devastation."

In the small town of Vilonia in Faulkner County, strong gusts of wind wrenched houses off their foundations and flipped cars on top of the rubble. Sixty homes were destroyed in the county, and nine of the victims in the county lived on the same street, according to local broadcaster KARK TV.

In total, on Sunday about 31 tornadoes were recorded, which formed late in the day. At least six shelters were set up in Arkansas for survivors, while medical officials reported that at around 100 people in Arkansas suffered from injuries.

In Oklahoma and Iowa, one death each was reported.

"It's so heartbreaking. I've never seen destruction like this before," U.S. Rep. Tim Griffin told reporters after touring Vilonia. "I saw a Dr. Seuss book in the rubble. I saw a Spider-Man shirt in the rubble. It just breaks your heart."