The national police bomb squad was called out on Monday morning after a detonation in an apartment block in central Stockholm.
Police were called out to the building at the Mariatorget square on Södermalm at 3.37am after receiving reports from people hearing “a sound described as a powerful bang”, a statement said.
They were able to confirm that the detonation had caused damages to the staircase area and an apartment door in the building, but said there was nothing indicating anyone had been injured.
“Police at the scene are making sure that those who have to leave their apartments can do so even though the national bomb squad and forensic teams will be working in the stairwell,” police said.
It remained unclear on Monday morning what had detonated and why.