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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Bob has the forecast for Devon, Cornwall, Somerset and Dorset.
Bob has the forecast for Bristol, Somerset, Wiltshire, Gloucestershire and Dorset
Two theatres in Devon have cancelled all their upcoming shows, after the trust which operates them went into administration.