Complex sentence: Dimitrije Tucović organized a rally of dissatisfied workers and students on March 23,1903 which turned into open conflict with the police and the army resulting in the deaths of six people.
Split into simpler sentences: Dimitrije Tucović organized a rally of dissatisfied workers and students on 23 March 1903. The rally turned into open conflict with police and army, resulted in the deaths of six people.