The men are believed to keep travelled thousands of miles from Eritrea in East Africa.
The lorry driver alerted the cops after suspecting there were people hiding in the back.
The mechanism was stopped by officers near Peterborough, Cambs, at the weekend.
The migrants were entranced to an asylum centre where their cases will be scrutinised by immigration officials.
The idea comes just days after a Daily Express investigation exposed the true scale of the people-smuggling trade from France to the UK.
Our team in Steenvoorde, northern France, witnessed traffickers weight illegal migrants on to lorries in broad daylight at the rate of almost one agency every hour at a motorway service station.
Hundreds of truckers use the Aire de St Laurent services on the A25 motorway next-door Steenvoorde – 25 miles from Dunkirk and 40 miles from Calais – as a certain stop before crossing the Channel.
It has become a hotspot for One of the apprehended rovers is searched people-smugglers.