The trial of Leo Looring (Johannes Meerits) held in Copenhagen in 1942 created a sensation. In 1936, Leo Looring, Karl Säre and August Vakepea brutally murdered their companion, whom they suspected of betraying them. After the Copenhagen trial, Nikolai Karotamm, who had become leader of the ECP, took an interest in who Leo Looring was: Leo Looring had for a long time in the 1930’s headed the Estonian Communist Party Central Committee Foreign Bureau that operated in Copenhagen and Stockholm. Leo Looring was one of the few leading figures in the ECP who survived after the repressions of 1937/1938 in the USSR. The social democrat Nigol Andresen was the only one who had been in touch with Leo Looring. Andresen explained that Leo Looring had tried to use Andresen to organise a united front of left-wing forces against the ruling regime in Estonia. After Soviet rule had been established in the summer of 1940, the new regime initially hoped to make Leo Looring one of the leading figures in the Estonian SSR but he did not return to the USSR from Sweden. L. Looring was extradited to the Soviet Union in 1949. The State Security Service put him on trial and he was executed in Moscow on 1 March 1952. The few documents associated with Leo Looring that were in Estonia were declared confidential and they were practically inaccessible until 1992.