On 27 June 1980, Itavia Flight 870 (IH 870, AJ 421), a McDonnell Douglas DC-9 passenger jet en route from Bologna to Palermo, Italy, crashed into the Tyrrhenian Sea between the islands of Ponza and Ustica, killing all 81 people on board. Known in Italy as the Ustica massacre ("strage di Ustica"), the disaster led to numerous investigations, legal actions and accusations, and continues to be a source of controversy, including claims of conspiracy by the Italian government and others. A 1994 report found the cause of the crash was a terrorist bomb, one in a years-long series of bombings in Italy. The Prime Minister of Italy at the time, Francesco Cossiga, attributed the crash to being accidentally shot down during a dogfight between Libyan and NATO fighter jets.