09 April 1937,
Bilbao was bombed by Francoist troops. The bombing involved German and Italian air strikes and killed 30 people. Another 16 deaths and 40 injuries were captured by a train in the Uribarri neighbourhood tunnel. On the same day the Francoists also bombed the following villages: Amorebieta-Etxano, Areatza, Arrigorriaga, Bedia, Bermeo, Etxebarri, Galdakao, Gorbeia, Leioa, Ugao-Miraballes and Zeanuri.
Source:
Xabier Irujo, Atlas of Bombardments in the Basque Country (1936-1937) (Memory Collection).