Prosecutors in Germany have dropped their investigation into a comedian accused of insulting Turkish President Recep Tayyip Erdogan. In a statement on Tuesday, the prosecutors said they had not found sufficient evidence to continue the inquiry against Jan Boehmermann. In March, Boehmermann went on TV and recited a satirical poem that made sexual references to Erdogan, prompting the Turkish president to complain that he had been slandered. In their statement, however, prosecutors said "criminal actions could not be proven with the necessary certainty" to continue the case.