The scam first came to light in November, when border agents at the main Paris airport stopped a man who had travelled from Mali on a passport that did not belong to him, a police source told AFP on Thursday.

“He told us he had paid €7,000 to fly from Bamako to Paris with an authentic French ID document,” the source said.

Police uncovered the existence of a network in the Paris region that recruited French nationals with an immigration background to “lend” their identity papers in exchange for several hundred euros.

They then either sent their passports to somewhere in Africa by post or asked for a new passport from French authorities with the photograph of someone else.

Investigators believe at least 250 people signed up for travel papers from the criminals, who offered their services to clients in Mali, Ivory Coast and Cameroon, often via social media.

Border police on Tuesday arrested three men and four women on suspicion of running the operation in the Paris area. The suspects are all of Malian origin and aged between 24 and 55, the source said.

They are now hoping to identify those who shared their passports.