Nine people were arrested in Berlin on Sunday at a rally to commemorate German communists Karl Liebknecht and Rosa Luxemburg, who were during a socialist uprising in January 1919. The police said they arrested the nine, among a group of around 4,000 demonstrators, for throwing bottles and covering their faces at the annual ceremony in the Berlin suburb of Friedrichsfelde. Liebknecht and Luxemburg were murdered by far-right soldiers during an uprising 86 years ago, after transforming the left-wing Spartacus League into the German Communist Party. Luxemburg's body was dumped in a Berlin canal while Liebknecht's corpse was taken to a hospital by his assassins, who identified him as an "unknown dead Spartacist." The turnout for the rally is believed to rank among the lowest on record for what had been a state-sponsored tradition in former communist East Germany.