41.   Air sirens sounded periodically throughout the day Thursday before the evening attack in Belgrade, where schools, airports and most shops were closed.

42.   Air sirens sounded periodically throughout the day Thursday before the evening attack in the tense capital, Belgrade, where schools, airports and most shops were closed.

43.   Air-raid sirens sounded early Monday in the Yugoslav capital and other major Serbian cities, warning of possible NATO airstrikes.

44.   Air-raid sirens sounded Saturday in the Yugoslav capital, warning of possible NATO airstrikes.

45.   Air raid sirens also sounded late Friday in several other cities.

46.   Air raid sirens also sounded late Friday several other cities.

47.   Air raid sirens had sounded the warning of attacks late Monday.

48.   Air raid sirens sound again at dusk, possibly signaling a new wave of attacks.

49.   Air raid sirens sounded again in the Yugoslav capital at mid-morning.

50.   Air raid sirens sounded Friday night in Belgrade, signaling the possible start of more attacks around the capital.