The importance of the Far East Front gave Blyukher a certain degree of immunity from Stalin's purge of Red Army command, which had begun in 1937 with execution of
Mikhail Tukhachevsky—in fact, Blyukher had been a member of the tribunal that convicted Tukhachevsky. On 15 June 1938, three days after the head of the Far Eastern
NKVD Genrikh Lyushkov defected to Japan, Blyukher visited NKVD headquarters in Moscow, seeking information about the defector and about potential consequences of his disappearance. He met the deputy head of the NKVD,
Mikhail Frinovsky, who appears to have reassured him that he would not be held responsible for letting Lyushkov cross the Manchurian border. On 17 June, Frinovsky and the head of the Red Army political directorate,
Lev Mekhlis, were dispatched to the Far East to conduct mass arrests, and to spy on Blyukher. He was arrested on 22 October, by which time Frinovsky had been dismissed and the NKVD was effectively controlled by
Lavrentiy Beria. It was long believed that Blyukher was secretly tried, convicted of spying for Japan, and executed. In 1939 Chiang Kai-shek inquired about Blyukher's whereabouts in a meeting with Stalin, and asked if he could return to help the Nationalists. Stalin replied that the general had been executed for helping a Japanese spy. As early as February 1956, it was secretly reported to the party leadership, by a commission appointed to investigate the purges, that a former officer had seen Blyukher while he was under interrogation, and that "his whole face was swollen and covered in bruises." Unlike most prisoners subjected to this kind of torture, he did not sign a false confession, but after 18 days of torture, he died from his injuries, on 9 November 1938. His body was cremated the same day. The cause of his death was first reported in 1989, in
Izvestia. The officer who beat Blyukher to death has been named as
Lev Shvartzman. Blyukher was
rehabilitated in 1956. He continues to be a popular figure in Russia, and a documentary film on his life and several publications by family members have appeared. ==Honours and awards==