The leaders of the Left-SRs also hoped to gain the support of the left-communists, at odds with Lenin for his capitulation to the Treaty of Brest-Litovsk . The schism in the Bolshevik leadership, however, had settled by the end of the month and the Left-SRs could not count on the support of the former dissidents in their confrontation with the government in Congress. Seeking to secure a majority in the congress, on June 14 Lenin ordered the expulsion of the Mensheviks and the Right-SRs from the All-Russian Central Executive Committee (VTsIK) to undermine their chances of getting delegates. Despite pre-congress estimates that the left socialist revolutionaries would eventually have nearly as many delegates as the Bolsheviks, the Bolsheviks sent enough delegates with suspicious credentials to secure a large majority in congress, wiping out the hopes of modifying government policy in congress. In this environment, the Third Party Congress took place, between June 28 and July 1, a congress that showed greater unity in the party and a certain euphoria for its growth — the number of affiliates had tripled in just three months - and in which greater hostility to the Central Empires and to maintaining peace with them was revealed. Spiridonova raised the provocation of the imperialist invasion to cause uprisings like those taking place in Ukraine, a position that was rejected by other delegates, who were not convinced of the disposition of the population to rise up against the occupiers. Opposition to maintaining the treaty, however, was in a majority among the delegates and the central committee weighed in on carrying out terrorist actions against the German representatives. In this tense atmosphere began the Fifth Congress of Soviets on July 4. The Left SRs, being in the minority (about 353 (30%) deputies, to the Bolsheviks’ 773 (66%) deputies), still openly opposed their former Bolshevik allies, for which they were expelled from the congress. On July 6, the German Ambassador Wilhelm von Mirbach was assassinated by Yakov Blumkin and Nikolai Andreev, on the orders of the Left-SR Central Committee. Initially the Bolsheviks reacted in disbelief, doubting the authorship of the crime. Felix Dzerzhinski himself, sent to the Moscow headquarters of the Cheka in search of the assassins, was arrested by the Left-SR central committee, gathered there, when he believed that the socialist revolutionaries were not involved. The intention of the party was not, however, to seize power and overthrow the Bolsheviks, but to force a confrontation with Germany , destroying the results of Brest-Litovsk.