Two of Amazon's key sites in Germany were the target of fresh walkouts by staff on Thursday in an long-running wage dispute.
The services sector union Verdi has called for full-day stoppages at Amazon's logistics centres in Leipzig and Bad Hersfeld.
Participation was "good," a Verdi spokesman told AFP, without specifying how many employees took part in the strike.
Amazon has a workforce of around 2,000 in Leipzig and 3,300 at Bad Hersfeld.
Amazon has a total of nine sites in Germany and has been regularly hit by walkouts over the past year.
Verdi has been trying for months to get Amazon to bring the pay of its 9,000 workers in Germany in line with wages in the distribution sector.
Amazon refuses, arguing that its distribution centres are logistic sites and that it pays its staff accordingly.
Wages in the logistics sector in Germany are lower than in the distribution sector.