The suspicion arose when seeds began to leak from an envelope, reports Smålandsposten.
"It's a little unpleasant and also a little strange," municipal councilor Åke Nyberg (M) told the newspaper.
The person who handled the letter closed the mailroom and called the police, the municipal councilor said.
At 2:30 p.m., the police finished their work at the scene and the cordons were lifted. The police have not yet announced what the letter contained and whether it was dangerous, reports SVT Småland.
Those who have been in contact with the letter, and who were initially isolated, have not shown any symptoms.
