Campers joined police to search through the night for the missing boy, who was last seen at a campsite at Thistledown Farm in Nympsfield, near Stroud at around 7pm last night.
Police said a more extensive hunt was due to start as daylight breaks.
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Unsettled outlook for the rest of the weekend
Unsettled, windy and showery outlook
Lifeguards are back patrolling some of the west country's busiest beaches from today for the summer season.