In September 1943, German troops occupied Grenoble, escalating the conflict with the clandestine movements. On 11 November 1943 (the anniversary of the armistice of 1918) massive strikes and demonstrations took place in front of the local collaboration offices. In response, the occupiers arrested 400 demonstrators in the streets. On 13 November, the resistance blew up the artillery at the Polygon, which was a psychological shock for an enemy who then intensified the repression. On 25 November, the occupiers killed 11 members of the Résistance organizations of Grenoble. This violent crackdown was nicknamed "Grenoble's Saint-Bartholomew". From these events, Grenoble was styled by the Free French Forces the title of "Capital of the Maquis" on the antennas of the BBC.