On this day ...

... seventy years ago - April 26, 1937 -, German soldiers of the "Legion Condor" bombed the small Spanish town of Guernica. It was the Nazi Reichsluftwaffe´s first military strike abroad, and the first air raid on an extensive civil area in military history, completely destroying the center of Guernica, plastering the town with a deadly carpet of incendiary bombs, grenades, and shots fired from aircraft weapons upon the fleeing men, women and children.

To this day, it remains unclear how many casualties this air raid caused. At the time of the attack, many refugees from the Spanish Civil War had fled to Guernica. The highest estimate is around 2000 casualties, while according to other sources around 300 people were killed - burnt, torn to pieces, or shot.

The account of an eye witness, whose estimate of casualties ranges closer to 2000, captures the horror which statistics just won´t adequately describe:

I had arrived in Bilbao on April 24 and on the next day had gone to Mass with the Foreign Secretary and his family, spending the rest of the day in his office. The morning of the 26th I spent quietly at the office of Asistencia Social, discussing in outline the plans for evacuation. In the afternoon I made my way down to La Prensa where a group of journalists had invited me for a drink, among them Philip Jordan and George Steer, who during the next few weeks were to prove towers of strength and encouragement to me. A day begun so quietly was to end in indescribable horror and dismay.
"A raid's coming up," said Jordan. "Do you want to go down to the shelter?" I shook my head, so we went outside. Phil's ear had caught the sound of bombers in the air, although there had been no warning. Across the hills to the east the air was alive with Heinkels as wave after wave drove in from the sea. They were followed by Junkers. Horror-striken, the Basques amongst us shouted, "Guernica! they're bombing Guernica!" It seemed incredible that such a monstrous thing could happen to this quiet little market town, renowned from time immemorial as the home of Basque liberation where, before the famous oak tree, rulers of Spain had traditionally sworn to observe Basque local rights. Helpless to do anything we watched from the hills. Until nearly eight in the evening, incendiary bombs and high explosives rained down every twenty minutes. The town was open and defenceless; it was crowded with market day visitors and as people fled from the destruction they were dive-bombed and machine-gunned from the air. The roads out of the town were jammed with dead and injured: 1,654 killed; 889 injured.
(From the autobiography of Leah Manning, A Life For Education)

Here you can find more on the bombing of Guernica. And, of course, on Wikipedia.