On 12 December 1969, a bomb exploded in the Milan office of the National Agricultural Bank in Piazza Fontana. 17 people were killed and 88 others wounded. Among those interrogated as suspects was anarchist railway worker Giuseppe Pinelli. On the night of 15 December, Pinelli died from a fall from a fourth floor window of the police headquarters. Theories of what caused Pinelli's fall included murder, suicide, and an accident due to loss of consciousness. On 3 July 1970 judicial authorities closed the case as an accidental death. A second inquiry in 1975 confirmed this by ruling Pinelli's death due to an "active illness". The 1975 tribunal further found that Calabresi was not in the room at the time of Pinelli's death. However, elements of the far left did not accept the determination.