Witnesses said the children were swept away in the Meramec River Sunday evening at Castlewood State Park, said Tracy Panus, a spokeswoman for St. Louis County police.
They six were part of a group of about 50 youngsters with the St. Louis Dream Center, an interdenominational church that was celebrating a volunteer appreciation day with a barbecue and swimming in Castlewood State Park southwest of St. Louis.
The body of the final victim was recovered around 6 a.m. Monday, about 12 hours after the children disappeared, said Becky Haskamp, a dispatcher for the Missouri State Water Patrol.
Two of the waders were alive when they were pulled from the water, but one died during the night at a hospital, Haskamp said. She said the only survivor remained hospitalized Monday and had no details on the child's condition.
Rescue workers were hampered by inconsistent reports about how many children were missing, Panus said.
Parents said the youngsters the children could swim, Panus said.
There was no immediate response to calls seeking comment from the St. Louis Dream Center, based in North St. Louis, the AP reports.
The center's Web site describes it as "an inner-city church with a heart to reach out, bringing hope and healing place to a hurting world." It was started in 2000, based on the Los Angeles Dream Center, to be a multiracial, interdenominational church offering social services including a teen drop-in center and programs for the homeless.
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