From Washington Post:

The problem has been rendered vividly in recent weeks by a pair of deadly assaults that each paralyzed a European capital. In Paris and Copenhagen, the attacks were carried out by former small-time criminals turned violent extremists who obtained military-grade illicit weapons with apparent ease.

In contrast with the free-firing United States, Europe is generally seen as a haven from serious gun violence. Here in Denmark, handguns and semiautomatic rifles are all but banned. Hunting rifles are legally available only to those with squeaky-clean backgrounds who have passed a rigorous exam covering everything from gun safety to the mating habits of Denmark’s wildlife.