At this point, Yugoslavia's refusal to join the Axis camp incurred Hitler's wrath. The Yugoslavian government under Regent Prince Paul had initially been in favour of joining Germany. But a "coup d'état" had toppled the government, deposed the Regent, and proclaimed the teenage Peter II as king. In response to this, Hitler ordered the invasion of Yugoslavia, "Operation Punishment" ("Strafgericht"). During the bombing of Belgrade, the center of the Yugoslavian capital was destroyed and 15,000 people killed and made homeless. The bombing started 6 April and continued for four days until 10 April.