The order from the highest authority was clear: “On the command of the guide ... the general line Lens – Béthune – Aire – St. Omer – Gravelines (canal line)

not

to be crossed ”, radioed the high command of the German Army Group A on May 24, 1940 at around 12:45 p.m. With this famous "halt" order, the German tank commanders were instructed to immediately stop their advance on the port of Dunkirk, where around 400,000 British and French troops had fled. This "stop command" and its consequences are among the most controversial actions of the Second World War.