The RSK leadership decided to retaliate against Croatia by ordering the artillery bombardment of Croatian urban centres . On 2 May , the RSK military attacked Zagreb and Zagreb Airport using eleven M-87 Orkan rockets carrying cluster munitions . The attack was repeated the next day . Six civilians were killed and 205 injured in the two attacks , while a policeman was killed defusing one of 500 unexploded bomblets . United States ambassador to Croatia , Peter Galbraith called the attack a declaration of an all-out war
attacked Zagreb
Zagreb rocket attacks
Operation Flash