A year-long ploy which included bugging a bar in the Paris suburbs has helped French police take down a suspected asylum seeker smuggling gang.

The Pierrefitte connection – as the gang is known – made up to 3 million euros smuggling up to 1,000 people in the back of trucks bound for places such as Dover and Folkestone.

For the last 12 months officers have kept close tabs on the group, including bugging the bar where members of the smuggling gang met to discuss their plans.

The investigation came to a head in a series of raids earlier this month with seven people arrested, a French police chief told the PA news agency.

The crime group smuggled asylum seekers living in Paris or nearby out to the highway where they were loaded onto trucks in the south east of the capital.

The gang’s method reflects a shift of smugglers starting journeys farther and farther from the border in the belief that vehicles are less likely to be searched, Supt Jean Arvieu told PA.

He said he has seen evidence of people seeking asylum boarding trucks from as far away as Bordeaux – more than 500 miles from Calais.

Mr Arvieu is deputy chief of The Central Office for the Suppression of Irregular Immigration and the Employment of Untitled Foreigners (Ocriest), part of French Border Police.

Ocriest's work includes targeting criminals trying to smuggle people into Britain, whether by road or on small boats.

He said: “They were operating at night.

“During one year of investigation we could count about 500 to 1,000 passages or attempts to cross the Channel.”

Those being smuggled had to pay 3,000 euros for a place aboard a truck and the crime gang is thought to have made between 1.5 million and 3 million euros from the operation.

Officers refer to the group as the Pierrefitte connection – a reference to its links to the northern Parisian suburb Pierrefitte-sur-Seine.

'We could count about 500 to 1,000 passages or attempts to cross the Channel'

Those seeking refuge would have been living in squats in the French capital or the surrounding area and were mostly men aged between 20 and 35, Mr Arvieu said.

However, he added: “One night we could see a kid loaded in a truck and sometimes we have families. This is problematic.

“It shows that smuggling by trucks to Great Britain is still a reality.”

With winter approaching and weather conditions getting worse, Mr Arvieu expects numbers of smuggling attempts in trucks to rise as small boat crossings become more dangerous.

Asked whether he thinks Brexit will have an effect on people smuggling via the Channel, Mr Arvieu said it was difficult to say.

Seven people have been arrested in connection with the Pierrefitte connection and three individuals have been remanded in custody while the investigation continues.

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