The Romanian driver of the lorry has been arrested by the French border police who will investigate.
Dave Hutchinson, Border Force Deputy Director for South East & Europe, said: “The dangers of using refrigerated lorries and sealed tankers in this way are self evident. The consequences are potentially fatal."
In 2000, 58 Chinese immigrants died after being sealed into the back of a lorry which was stopped at Dover.
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Friday's forecast for the east of the region
Emergency services and volunteers have been involved in a major search for a missing Rochester teenager who has not been seen since Tuesday.
Friday morning's forecast for the west of the region