 Ukrainian President Petro Poroshenko expressed condolences to the victims, whom he described as Ukrainian citizens, stating that the Prosecutor General's Office of the Autonomous Republic of Crimea had initiated criminal proceedings under the article "act of terrorism".The Secretary General of the Council of Europe Thorbjørn Jagland and Secretary-General of the United Nations António Guterres also expressed condolences.Some newspapers described the attack as "Russia's Columbine", a reference to the 1999 US high school massacre.