During the Years of Lead, the PCI strongly opposed the terrorism and the Red Brigades, who in turn murdered or wounded many PCI members or trade unionists close to the PCI. According to Mitrokhin, the party asked the Soviets to pressure the Czechoslovakian State Security (StB) to withdraw their support to the group, which Moscow was unable or unwilling to do. This as well as the Soviet invasion of Afghanistan led to a complete break with Moscow in 1979. In 1980, the PCI refused to participate in the international conference of communist parties in Paris although cash payments to the PCI continued until 1984.