 Anglo-American bombers first attacked Bucharest on 4 April 1944, aiming mainly to interrupt military transports from Romania to the Eastern Front.Lasting for two hours, the operation destroyed hundreds of buildings and killed or injured over 5,000 people according to unofficial statistics.Following King Mihai I's 23 August coup against Antonescu, the "Luftwaffe" retaliated from 23–25 August, and destroyed several buildings in Bucharest until their base just north of the city in Otopeni was itself bombed by the USAAF and RAF.