About 900,000 migrants arrived in Germany between 2015 and 2016, most of them from war-torn countries like Syria, Iraq and Afghanistan; since then, however, their number has shrunk significantly.
At the height of the migration crisis, German authorities failed to investigate thousands of pieces of evidence suggesting that war criminals were seeking asylum in the country, Bild reports.
Germany became one of the countries most affected by the migration crisisin Europe, which broke out in 2015 with a huge influx of people fleeing armed conflicts in the Middle East and North Africa.