A powerful explosion hit a five-storey building in Linköping, southern Sweden, on Friday morning, authorities said in a press release.
It destroyed windows and balconies and left the ground covered in debris, said the statement.
At least twenty-five people were lightly injured, said police. They have been taken to hospital for treatment.
Authorities are not planning on evacuating any more people.
The cause of the explosion is unknown but Sweden’s national bomb squad was on its way to the scene.
Police said they have opened a criminal investigation into the incident.
"There is nothing that indicates that this incident is terror-related, we do not see that," said police spokeswoman Asa Willsund.
"We think that it occurred outside," Willsund said of the explosion. "We estimate that there are 25 people with minor injuries - no serious injuries or deaths."
Pontus Johansson, a 21-year-old engineer who lives near the building told Reuters he was in the shower when he heard a loud noise.
"First I didn't think it was anything bad, then I saw the neighbour's window was broken so I left our apartment and saw the chaos outside," he told Reuters.