The National Weather Service said it had received reports "well into the double digits" of twisters touching down in six counties. Numerous tornadoes were reported from South Dakota south into Oklahoma as forecasters scrambled to keep issuing warnings.
The new storms forced rescuers to abandon search efforts Saturday in southwest Kansas, where crews had spent the day hurrying through the wreckage from Friday night's giant tornado.
That massive twister — as much as a mile wide — wiped out entire neighborhoods and spared almost nothing in its path. In the town's business district, all but a few buildings were destroyed, CBS News correspondent Drew Levinson.
"There's a couple of structures that aren't as heavily damaged as others, but it was wide enough to completely get the entire city of Greensburg," says Maj. Gen. Todd Bunting of the Kansas National Guard. "Absolutely catastrophic damage."
Friday's weather was blamed for nine deaths in Kansas, a figure authorities feared could rise even before the latest twisters.
City Administrator Steve Hewitt estimated 95 percent of the town of 1,500 was destroyed and predicted rescue efforts could take days as survivors could be trapped in basements and under rubble.
Among the only structures that survived was the Bar H Tavern, the town's lone bar. It was briefly converted into a morgue.
Survivors picked over the remnants of their homes and possessions, still dazed by the twister's strength and scope.
"We could see everything flying around. It sounded like diesel engines, jet engines. It was just horrible," one survivor told CBS News.
The town, previously best known as the home of the world's largest hand-dug well — 32 feet in diameter, 109 feet deep when it was finished in 1888 — was a nightmare of splintered homes and smashed vehicles, the air redolent with the smell of sap from trees stripped of bark.
"We want everybody to know, and I plead to the American people as well as the people here in Kansas, this is a huge catastrophe that has happened to our small town," Hewitt said. "All my downtown is gone. My home is gone. My staff's homes are gone. And we've got to find a way to get this to work and come to work every day and get this thing back on its feet. It's going to be tough."
Among the funnel clouds Saturday were a series of half-mile wide "wedge" tornadoes — similar to the one that devastated Greensburg on Friday night, meteorologist Mike Umscheid said.
Umscheid said the slow-moving storm system would likely spawn severe weather early into Sunday morning.
"It looks like it's going to be another long night," he said.
A twister hit a high school in Sweetwater, Okla., late Saturday, and storm spotters reported damage to nearby residences in the far western Oklahoma town.
There were injuries, though the number and severity weren't clear because communications had been knocked out, a spokeswoman for the Oklahoma Highway Patrol said. Several tornadoes were reported in that area and several other parts of the state.
Greensburg residents said they heard tornado sirens — a common feature of towns in "Tornado Alley" — about 20 minutes before Friday's storm hit.
Even with that heads-up, Frank Gallant had no place to go. Gallant, who uses a wheelchair, had no basement, so he moved to the center of his house with his miniature pinscher, No. 5.
"You just hope you've lived up to the Lord's expectations, and you're going to the good place and not the bad," said Gallant, 47.
Terry Gaul, a salesman on his way back from a business trip, pulled into a John Deere dealership with his partner to wait out what they thought was a hailstorm.
"The next thing we heard was this loud rumble," said Gaul, his red polo shirt stained with blood and his face crosshatched with cuts. "There were these two John Deere combines sitting there, and the next thing I know, they started rocking. Then we started spinning like a windmill, and I said, 'Oh, boy, it's all over with now.'"
The tornado rolled Gaul's van, throwing him into the back seat. When he came out, he noticed something missing.
"I never seen where those two combines went," he said.
Weather Service meteorologist Larry Ruthi said the path of damage was 1.4 miles wide, estimating it would be classified a "upper F-4 or an F-5" tornado, the strongest possible.
Jose Peraza said he was driving his oil rig into town when he heard the siren and driving hail started pounding the area. He pulled over and hid with several other people in a convenience store freezer.
He said the storm ripped the side off the freezer, and when he came out he found the twister had thrown his truck — weighed down by 40,000 pounds of oil — "like nothing."
The dead included eight in Kiowa County and one in nearby Pratt County, said Sharon Watson, a spokeswoman for the Kansas Adjutant General's Department. She said officials are looking into reports of two other storm-related deaths.
State Rep. Dennis McKinney, the Kansas House minority leader, said he and his daughter hid in the basement while the storm destroyed his home. He helped search homes for survivors but noted "the inspections didn't take that long because in the western part of town, there weren't many homes left to inspect."
A mandatory evacuation was ordered, he said. Gov. Kathleen Sebelius declared a disaster emergency for Kiowa County and planned to tour the area Sunday, said her spokeswoman, Nicole Corcoran. The state sent 40 National Guard soldiers to help.
The White House said President Bush was briefed on the situation, and a spokeswoman for the Federal Emergency Management Agency said FEMA was preparing to send aid.