Stowaways including 11 men, three women and a 15-year-old boy were discovered in the back of a lorry at a service station in Somerset.
Police were called when a motorist heard banging on the side of the truck. A German man has been arrested on been arrested on suspicion of facilitating the unlawful entry of people into the UK.
ITV News Wales and West of England Correspondent Rupert Evelyn reports
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