Vitaly Konstantinovich Kaloyev (, ; , ; born 15 January 1956) is a Russian former architect and convicted murderer who was found guilty of the premeditated killing of an air traffic controller after his family died aboard BAL Bashkirian Airlines Flight 2937, which collided with DHL International Aviation ME Flight 611 over Überlingen, Germany, on 1 July 2002. Kaloyev held Peter Nielsen (16 August 1967 – 24 February 2004), the sole air traffic controller in Switzerland who was handling traffic the night of the collision, responsible. In 2004, Kaloyev travelled to the Swiss town of Kloten, where he killed Nielsen, who had since retired from air traffic work. Later, after his release from prison, Kaloyev was appointed deputy minister of construction of North Ossetia–Alania. In 2016, upon retirement from the local Ossetian government, Kaloyev was awarded the highest regional medal by that government, the medal "To the Glory of Ossetia". The medal is awarded for the highest achievements, improving the living conditions of the inhabitants of the region, for educating the younger generation and maintaining law and order. Background Vitaly Kaloyev had lost his wife Svetlana Kaloyeva () and two children, 10-year-old Konstantin () and 4-year-old Diana () in the Überlingen mid-air collision in 2002. Yuri Kaloyev, the brother of Vitaly Kaloyev, reported that he suffered a nervous breakdown following the loss of his family. Vitaly Kaloyev participated in the search for the bodies and located a broken pearl necklace owned by his daughter, Diana. He also found her body, which was intact, as some trees had broken her fall. Svetlana's body landed in a corn field, while Konstantin's body hit the asphalt in front of an Überlingen bus shelter. Kaloyev spent the first year after the accident lingering at the graves of his family and building a shrine to them in his home. At the memorial service for the first anniversary of the tragedy, he asked the head of Skyguide about the possibility of meeting the controller who had been responsible for the disaster, but he received no response. Kaloyev then hired a Moscow private investigator to find Nielsen's address outside Zürich, before travelling to the former air traffic controller's home in Kloten. Murder of Peter Nielsen On the afternoon of 24 February 2004, he set off for Nielsen's house. A neighbour spotted Kaloyev and asked what he wanted. He waved a piece of paper with Nielsen's name on