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.