Partisans during the Second World War frequently used tactics recommended by the CPB, but were most frequently used during Operations Rail War, Concert and Bagration. In fact, Ilya Starinov, one of the primary saboteurs, helped organise the latter two operations. Explosives were heavily used during the rail war to destroy German rail lines. Many partisans used explosives which had been developed for the express purpose of the rail war, but others used grenades or improvised explosive devices.