UPDATE: 16 confirmed dead from southwestern AR floods

CADDO GAP, Ark. (AP) - The rugged river valleys of the Ouachita Mountains in southwestern Arkansas are a draw for hikers and campers, but early Friday morning, they turned into a trap.

Heavy rains triggered flash floods along the Caddo and Little Missouri rivers, swamping campers sleeping along the rivers' banks.

Authorities say at least 16 people were killed and family members have reported more than three dozen people missing after the normally peaceful rivers rose as much as eight feet in an hour.

The National Weather Service says more than seven and a half inches of rain fell and one river gauge shows the water rising more than 20 feet overnight.

State police describe the affected area as "very wide" and it's not clear exactly how many people may have been there. The National Guard has dispatched helicopters to help rescue efforts, because much of the area is now inaccessible by land.

Floods have eroded or blocked some roads, and parts of the valley are so steep and craggy that the only way out is to hike downstream.

Tommy Jackson, public information officer, Arkansas Department of Emergency Management says deadly flooding occurred in campgrounds in southwestern Arkansas.

Jackson adds that rescuers are still searching for anyone trapped by the flooding and that searches are still underway along the Little Missouri River in Montgomery and Pike counties.

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