A method (20) performed in a network node (4) is provided for alerting about failure of an unmanned aerial vehicle (2). The method (20) comprises receiving (21) a failure report from an unmanned aerial vehicle (2), obtaining (22) an estimated crash point for the unmanned aerial vehicle (2), and sending (23), based on the obtained estimated crash point, warning signals to communication devices (3) residing within a defined area. Methods in an unmanned aerial vehicle and in a network entity, and a network node, unmanned aerial vehicle, network entity, computer programs and computer program products are also provided.