Officers selected the German-registered van which was carrying insulation boards for further examination.
A heart beat detector gave a positive reading and officers carried out a detailed search during which they found a concealed box.
After forcing open the box, they discovered it contained lighting, fans and seven Sri Lankan immigrants.
The 51-year-old driver of the van appeared before the French courts where he was jailed for four months for facilitating people smuggling.
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Wednesday's lunchtime forecast for east of the region
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Comedian Peter Kay has cancelled Peter Kay's Live Arena Tour and Dance for Life shows due to unforeseen circumstances within his family.