HUNTSVILLE, TEXAS (AP) -- A 13 year old boy who never returned from a map-reading exercise in the Sam Houston National Forest has been found alive.

The junior ROTC member appeared unharmed Monday morning while sitting in the back of an ambulance.

Searchers used horses, dogs and a helicopter to comb through the massive national forest.

The boy was reported missing about 5 p.m. Sunday.

Temperatures before dawn Monday had slipped below freezing in the area, where the search went on through the night.

The boy had a map and a compass when he went into the woods shortly before 11 a.m. Sunday.

The name of the boy was not immediately released.

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