At least 16 people, including some children, were killed Friday after flash floods swept through their remote Arkansas campsites following a heavy rain, according to Gov. Mike Beebe.
About 60 campers were rescued by emergency workers, another two dozen hospitalized, the Associated Press reported, citing authorities. Dozens more are still missing and feared dead.
"About one-thirty, two in the morning, we started hearing children and women screaming and crying," said Crystel Hofer, who was asleep in her cabin when the water came raging through. "So we went to the door and opened the door and they were trying to come up the hill to where our cabin was to escape the rising water."
"It's a terrible tragedy and we're doing all we can to hopefully find some folks and bring some people back who are stranded out there," said Matt DeCample, spokesman for Gov. Beebe. "We've got a lot of state and local folks pulling together. This is an unprecedented tragedy out in this part of the state. It's a very rural but close-knit portion of Arkansas."
The area is still heavily flooded and searches are expected to take at least two days.
The Caddo and Little Missouri rivers -- two normally gentle waterways -- rose by 20 feet overnight, engulfing the hikers and campers who were spending the night in tents along the rivers in the isolated Ouachita Mountains.
"Within ten minutes the water had rose and campers were floating down," Hofer told ABC News. "If they didn't get out of their camper within five, ten minutes, they weren't getting out."
The 54-unit campground was quickly inundated with water, which was rising as quickly as 8 feet per hour. The water was so violent it overturned RVs and peeled asphalt off the roads.
"There was a lot of devastation in there, where it's coming along this river, there's vehicles that's overturned, there's cabins washed off their foundations," said Capt. Mike Fletcher of the Arkansas State Police Department.
The area affected, the Albert Pike campground, is managed by the U.S. Forest Service and is about 75 miles west of Little Rock. It is a popular camping area, due in part to its secluded location. Officials say they expect more deaths but do not yet have a full count on the number of people at the site or missing.
"We don't know who was in there last night," State Police spokesman Bill Sadler told the Associated Press. "This is a very wide area."
Brigette Williams, spokeswoman for the American Red Cross in Little Rock, told the Associated Press that between 200 and 300 people were believed to be in the area at the time of the flooding. She did not know how many of those were campers and how many were local residents.
DeCample said people there would have had "very little warning or alerts" because the flooding occurred while most people were sleeping. And because the area is so remote and terrain so rugged, officials believe that campers would have had to hike downstream in the dark to escape the valley, making the chances of survival for some even slimmer.
The Little Missouri west of Caddo Gap stood at 3 feet Thursday, but after 7.6 inches of rain fell in the area overnight the level jumped to 23.5 feet by Friday morning. It later dropped to 11.5 feet.
Searchers were working along the Little Missouri River in Montgomery and Pike counties and the National Guard dispatched helicopters to help in the rescue.
"We're just in the process of right now, trying to see if we have anyone to be rescued along the river there, and uh, also in a recovery stage," said Capt. Fletcher.
Officials were also bringing in a refrigerated truck to serve as a temporary morgue and downstream Glenwood police and fire crews monitored river debris moving beneath a highway overpass.
Two Shreveport, La., families were at the Albert Pike campgrounds when the floods hit, a family friend told ABC affiliate KTBS.
A 5-year-old member of one family was swept away by flood waters and the father and a 2-year-old child were missing, said Tonya Rabalais of Shreveport.
The father of the other family -- which consisted of a husband, wife and three children -- was missing, Rabalais said. The mother of the first family and four members of the second family survived.
The Associated Press contributed to this report.