When an extra 60,000 workers were called for in the summer of 1947, a wave of potential workers flooded into West Germany to avoid the mines including many citizens who would otherwise prefer to live in the communist East. Workers who began as volunteers were turned into forced labourers. In an effort to increase the number of labourers, women were increasingly recruited to the non-segregated mines, many of whom brought or were infected with venereal diseases, and were sexually exploited by the Russian guards.