ZAGREB, Croatia—A military drone that apparently flew all the way from the Ukrainian war zone over three European NATO-member states before crashing in an urban zone of the Croatian capital was armed with an explosive device, Croatia’s defense minister said Sunday. The Soviet-made aircraft crossed Romania and Hungary before entering Croatia, slamming into a field near a student dormitory late Thursday. About 40 parked cars were damaged in the large explosion, but no one was injured. “Traces of explosives and clues suggesting that this was not a reconnaissance aircraft were found. We found parts of an air bomb,” Croatian Defense Minister Mario Banozic said at the crash site. He said that this further raises a question about whether the drone belonged to Russia or Ukraine. “There are elements that indicated it could have come from both,” he said. Air crash investigators have pulled most of the drone’s remaining parts from …