 Complete the following phrase:  On 30 January 1927 a small number of armed members of the Frontkämpfervereinigung were involved in a confrontation with a much larger group of unarmed members of the left-wing Republikanischer Schutzbund. The Frontkämpfervereinigung activists opened fire and killed an adult and a six-year-old boy. When they were found not guilty on grounds of self-defence by a jury, the socialists organised a general strike which led to the 