The suspected object found in the Skälby area in Västerås during the night against Friday was a hand grenade that was assessed as live, the police report.
The police are categorizing the incident as an attempt at general endangerment and a crime against the law on fire hazardous and explosive goods. No suspect has been detained.
At 07:30, the national bomb squad neutralized the hand grenade.
The police cordoned off a larger area, which also included parts of a school. Several residents in the vicinity were evacuated, but after the grenade was handled, they were able to leave their homes under controlled forms.
The site where the hand grenade was found will continue to be cordoned off pending a technical investigation.