According to media reports, it is about one or more suspected hand grenades, something the police do not want to confirm. Not even after the object was detonated late on Sunday evening.
The object was handled as if it were live.
"The controlled detonations went according to plan and no person or property has been damaged," the police write on their website.
Some of the residents were told to stay in their apartments while others were taken out, prior to the detonation, by the rescue services with the help of a turntable ladder.
The incident is being investigated as attempted general endangerment, gross unlawful threats, and offenses against the law on fire hazardous and explosive goods.
No one has been arrested.
The alarm came just before 6 pm on Sunday.
