The owners of a lorry found containing 15 people near Ilminster take incidents of human trafficking "very seriously," a spokesperson said.
The Thermotraffic spokesperson added: "At the moment we are in close contact with the British public authorities and support them to investigate the situation."
A German national has been arrested on suspicion of facilitating the unlawful entry of people into the UK. He is understood to be the driver of the lorry.
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