Police in the Swedish city Malmö have reported that criminals in the city are using 3D printers to make working guns.

The problem for the city’s authorities is that under Swedish law it is not a crime to construct or hold a 3D printed gun’s impotent individual parts.

It is only when they are assembled into a working firearm are they in violation of the Arms Act, which is a situation Malmö’s police chief, Stefan Sintéus, is uncomfortable with.

“It is obvious that the aim is to put the pieces together into a weapon. The only thing missing is a gun barrel and a bolt, so I call for a discussion of the limits on when it counts as a crime,” said Sintéus in an interview with Swedish news programme, Skane.

The guns were seized in January and February of this year and were later tested, and proved to be working, at the National Forensic Centre.

Police reported finding one of the 3D printed guns during a city-wide criminal sweep, while the other firearm was discovered in a Malmö parking garage.

Both guns are reported to have been constructed in the same way: by disassembling a traditionally made gun, scanning the parts, and re-constructing them via a 3D printer, which are then assembled into a finished weapon.

According to Sintéus engineers performed test firings of the weapons on six different occasions, and can confirm they are indeed in working order. The firearms therefore now qualify as illegal weapons.

Sintéus’ comments make it pretty obvious that the Malmö police department believe 3D printed guns ought to be restricted in the same way ordinary guns are.

He also noted that while these incidents occurred in Malmö, 3D printed guns are increasingly being used by savvy criminals and the trend was “more common in Europe”.

Like it or not, we are reaching a stage where we will have to legislate for 3D printed guns, as well as their constituent parts.

“It’s not possible to criminalize a 3D printer, but it is nevertheless true that we now have people in the criminal environment that have this kind of weapon,” said Sintéus.