Explosion rocks Stockholm residential building

An explosion damaged a residential building in central Stockholm on Monday, police said, and while no injuries were reported it follows a wave of criminal bombings in the country.

Images published by Swedish media showed damage to the building's facade, the front door demolished and broken glass and debris scattered on the ground.

Several nearby cars were also damaged by the blast, the cause of which was not known, in the affluent neighbourhood of Ostermalm.

"At this time it's not possible to say whether the explosion occurred in or outside the building," a police spokeswoman told newspaper Aftonbladet.

Authorities were alerted to the explosion shortly after 1:00 am local time (0000 GMT), and the building was evacuated shortly after.

A preliminary investigation has been opened into "devastation endangering the public." Two hours later, around 3:00 am, another blast occurred outside a nightclub in Uppsala, some 70 kilometres (40 miles) north of Stockholm, although no link between the explosions has been established. No injuries were reported.

Ranked among the world's richest nations, Sweden has typically low levels of violence compared to other Western countries.

But the Nordic country has been experiencing a surge in gang related violence - often linked to drug-trafficking - in recent years.

In addition to shootings that result in dozens of deaths and injuries every year, rival groups have begun to routinely use explosive devices to intimidate their adversaries, including hand grenades and thermoses packed with explosives.

From January until November 2019, 236 explosions were reported, according to the Swedish National Council for Crime Prevention, though few have resulted in serious injuries.