NATO's aerial bombing of FR Yugoslavia in 1999, an answer to the Yugoslav campaign of ethnic cleansing in Kosovo, included targeted aerial bombing throughout Serbia, notably of targets in Belgrade, Novi Sad and Niš. In addition to military casualties, there were at least 500 civilian casualties. Despite the NATO campaign appearing to violate NATO's charter, the UNSC rebutted the case on March 24 and March 26, 1999. In addition to purely military targets NATO targeted the national power grid (leaving many cities in the dark), water purification plants, oil refineries, fertilizer factories, and a petrochemical plant in Pancevo. The 78-day bombing campaign is assessed as having been an 'economic catastrophe', cutting the Yugoslav economy in half.