In 1999, an armed confrontation between Albanian separatists from the Kosovo Liberation Army and the Serbian army led to a bombing of what was then the Socialist Federal Republic of Yugoslavia, consisting of Serbia and Montenegro, by NATO forces. The operation was undertaken without the approval from the UN Security Council and was based on the allegations by Western countries that the Yugoslav authorities were allegedly carrying out ethnic cleansing of Kosovo Albanians. NATO airstrikes continued from March 24 to June 10, 1999 and claimed the lives of over 2,500 people, including 87 children.