Four illegal immigrants were stopped from entering the UK in a lorry heading for Lincoln by Border Force officers.
The two men and two women, from Vietnam, were discovered at the Port of Calais on September 20.
The Bulgarian-registered lorry, loaded with potatoes heading to Lincoln, was waiting to board a ferry to the UK.
A sniffer dog found the group hiding in the lorry which was making a delivery to Mere Road, Lincoln.
The stowaways were dealt with by French border police and the vehicle was allowed to continued its journey.
Paul Morgan, of Border Force, said: “This incident shows why we base Border Force staff in France – to stop would-be illegal immigrants before they can reach the UK.
“Our strong presence in French ports like Calais helps protect the whole of the UK from people attempting to enter the country illegally.”
Border Force officers use sniffer dogs and carbon dioxide probes, heartbeat detectors, and physical searches to find people hiding in vehicles.