It was just before eight o'clock on Wednesday night that the explosion occurred at a gate to an apartment building.
No one was injured, but the stairwell was badly damaged.
Later that evening, four men aged 20-35 were arrested on suspicion of gross public destruction.
- The arrest took place in Malmö, but right now we can not go into any further details about the circumstances or the place of the arrest, says Nils Norling, spokesman for the police.
The police are looking for a connection
The explosion is the third since last Friday.
Most recently on Wednesday morning, a powerful explosion occurred outside an apartment building at Gröndal in Malmö.
Last Friday, an explosion took place at a residential building - also in Rosengård.
A bomb was also placed in Limhamn on Friday night, but it did not detonate.
- We continue to work intensively to look for possible connections between these different cases.
But at the moment, they are suspects and arrested for the case on Wednesday night, says Nils Norling.