 On 9 September the number of strikers was estimated to 20-25,000, at around fifty industry sites.On 10 September the German Reichskommissar Josef Terboven declared martial law in Oslo and the neighboring municipality Aker.Two union leaders, Viggo Hansteen and Rolf Wickstrøm, were sentenced to death by a court-martial, and immediately executed by an SS Sonderkommando led by Oscar Hans.