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
More top news
More than one in five school staff have had a false allegation made against them by a pupil, according to a survey.
Parents of obese children rarely spot that their child is overweight, doctors warn.
MPs are no longer MPs, just candidates again - Parliament has automatically dissolved and the 'short campaign' begins today.