Operation Hoarfrost, as the operation has been named, has been launched in order to reduce the number of explosions and shootings in Sweden and to increase the feeling of public safety.

The head of national police operations department Noa, Mats Löfving, took the decision on Sunday evening and said that the shooting of two teenagers the day before was “the final straw”.

“It is very rare that we use these special methods. There has to be an exceptional situation,” said Löfving.

No arrests have yet been made in connection with the shooting, which left one 15-year-old dead and another in hospital in a serious condition.

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The special national incident relates to violent crime in general and is not limited to any geographical area or specific incident. But Löfving said the shooting on Sunday was “the straw that broke the camel's back”.

“We saw a weekend in Malmö that is unacceptable, with an execution-like murder of a 15-year-old boy,” he told the press conference.

The special national incident means that a dedicated task force will look into violent crime, with the task force's commander-in-chief granted special powers to make decisions and allocate resources.

Four specific goals were outlined at the press conference: to reduce the number of explosions and shootings significantly, to reduce the number of people in criminal gangs through carrying out arrests and convictions, to seize weapons and explosives, and to increase the feeling of safety among members of the public.

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Stefan Hector, who will take on the role of commander-in-chief, said he expected that the special incident would have an impact “within six months”.

Prime Minister Stefan Löfven said he welcomed the measure, telling the TT news agency: “It is an important signal. Malmö residents should not feel that they are alone in this, but rather that this is a matter for the whole of Sweden.”

While Sweden's overall crime rate and homicide rate remains low from an international and historical perspective, there has been an increase in recent years in the proportion of murders linked to criminal gangs. And the number of explosions has increased, accounting for 162 of a total of 190 incidents of 'destruction causing public endangerment' last year.

The briefing explaining the special national incident followed an earlier press conference from Malmö police in which they outlined the measures underway in the city.

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Malmö's police chief said at that conference that both the victims of Sunday's shooting were previously known to police, and that an important step in crime prevention would be cracking down on the local drugs trade.

The role of the drugs trade in violent crime was a concern echoed by the prime minister, who told TT: “It is important that we as a society think about how we act, since organized crime survives to a large extent due to drug trafficking”.