BERLIN (AP) — Workers at a half dozen Amazon distribution centers in Germany and one in Italy walked off the job Friday, in a protest timed to coincide with "Black Friday" to demand better wages from the American online giant.

In Germany, Ver.di union spokesman Thomas Voss said some 2,500 workers were on strike at Amazon facilities in Bad Hersfeld, Leipzig, Rheinberg, Werne, Graben and Koblenz. In a warehouse near Piacenza, in northern Italy, some workers walked off the job to demand "dignified salaries."

The German union has been leading a push since 2013 for higher pay for some 12,000 worker...