In July 1918, a member of the Left SR, Yakov Grigorevich Blumkin, assassinated the German ambassador to Russia, Wilhelm von Mirbach, hoping that the ensuing diplomatic incident would lead to a relaunched revolutionary war against Germany. Seeking to defuse the situation, Lenin issued his personal condolences to the German Embassy. The Left SR launched a coup in Moscow, shelling the Kremlin and seizing the city's central post office, however their uprising was soon put down by Trotsky and two Latvian battalions. The party's leaders and many of their members were arrested and imprisoned, although the Bolsheviks showed greater lenience toward them the Left SRs than they had done to many of their other critics. On 9 July, at the Fifth All-Russian Congress of Soviets, a ban was declared on the party being involved in any of the country's soviets.