Police operation under way after explosion in Germany's Cologne

A police operation is under way after an explosion in central Cologne, Germany, the Bild newspaper reported on Monday.

Local police posted on X that a police operation was under way on the Hohenzollernring ring road and that residents should avoid the area.

The cause of the explosion was not immediately clear but Germany has seen an uptick in violent attacks recently.

Three people were killed and eight wounded last month in a knife attack at a festival in the western city of Solingen.

The suspect in the attack, which was claimed by the Islamic State group, was a Syrian man who had been slated for deportation from Germany.

Also on Monday, Germany began monitoring all of its borders to curb irregular migration.

* The story was produced with input from the news desk