This was a French special forces operation by the 4th Régiment de Chasseurs Parachutistes (4th Special Air Service) to disrupt German communications in the area between St Malo and Vannes in German-occupied north-western France in support of ‘Overlord’ (7 June 1944).
The operation was entrusted to 18 three-man teams, which were dropped blind by nine aircraft of the RAF’s No. 38 Group in 18 locations without any welcoming groups before operating to cut rail lines all over Brittany for two days. After this the teams were to remain active for eight to 10 days as they undertook secondary tasks including destruction of other communications targets, all types of German dumps and depots, power lines etc, as well as impeding the repair of the original targets. The groups were then to regroup at the SAS’s northern ‘Samwest’ or southern ‘Dingson’ bases. After the destruction of the ‘Samwest’ base on 12/13 June all the teams were instructed to report to the ‘Dingson’ base.
One of the operation’s more important successes was the prevention of the rail transport of Generalleutnant Richard Schimpf’s 3rd Fallschirmjägerdivision out of Brittany to Normandy.