The Piazza Fontana bombing; a bomb explodes at the headquarters of Banca Nazionale dell'Agricoltura (the National Agricultural Bank) in Piazza Fontana in Milan, Italy, killing 17 people and wounding 88. The same afternoon, three more bombs are detonated in Rome and Milan, and another is found unexploded.

The Piazza Fontana bombing was a terrorist attack that occurred on 12 December 1969 when a bomb exploded at the headquarters of Banca Nazionale dell'Agricoltura in Piazza Fontana in Milan, Italy, killing 17 people and wounding 88. The same afternoon, another bomb exploded in a bank in Rome, and another was found unexploded in the Tomb of the Unknown Soldier. The attack was carried out by the neo-fascist paramilitary terrorist group Ordine Nuovo, and possibly undetermined collaborators.

The Banca Nazionale dell'Agricoltura or BNA, was an Italian bank that existed from 1921 to 2000.

December 12 is the 346th day of the year in the Gregorian calendar; 19 days remain until the end of the year.