Kiev, May 16 : Air raid sirens were sounding in Kiev on Tuesday after the Ukrainian capital came under a heavy missile and drone attack. In video footages on social media, loud explosions could be heard as well as air defence systems were seen shooting down suspected Russian missiles, reports the BBC. Government messages warned people to keep away from windows as debris from intercepted missiles fell from the sky. Kiev Mayor Vitali Klitschko said some rocket debris had fallen in central districts, including on the city's zoo. There were reports of injuries. Serhiy Popko, head of the Ukrainian capital's military administration, described the latest barrage as being the "maximum number of attack missiles in the shortest period of time". "According to preliminary information, the vast majority of enemy targets in the airspace of Kiev were detected and destroyed," the BBC quoted the top official as saying. /IANS