Following a series of four explosions across Swedish cities within slightly more than an hour, bomb squad professionals were summoned by the authorities, the police said.
The country is currently grappling with efforts to control a rise in gang-related violence.
Just after 1:00 am local time (2300 GMT), police in Gothenburg received reports of two explosions at separate addresses, just 10 minutes apart.
"Both sites have been cordoned off and technical investigations are ongoing," police said, adding that the national bomb squad had been called to the scene.
"There are no reports of people being injured, only material damage," police added.
An hour later another two explosions were reported minutes apart in Norsborg -- a suburb south of Stockholm -- and in Nykoping, about 100 kilometres south of the capital.
In both cases, police said no one was hurt. All four blasts were at residential buildings.
Sweden has struggled to rein in a surge of shootings and bombings in recent years as gangs settle scores fuelled by the drugs trade.
But Gothenburg police told AFP it was too early as yet to speculate on a motive for the two blasts in the city.
According to police data, in 2022, Sweden saw 90 blasts and another 101 cases of attempted bombings or preparations for bombings.
As of August 15, 109 detonations had been recorded this year.
Police have previously said that bombs are mainly used to intimidate targets, while shootings are used to kill and eliminate enemies.
The country registered 391 shootings in 2022, 62 of them fatal, up from 45 the previous year, according to police data.
(AFP)
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