According to Expressen, seizures have been made and a man in his 40s has been arrested.
The national bomb protection has also been in place.
The police were initially secretive about the operation, which began at 2 p.m.
- It is an investigation matter, that is really all I can say, said Mats Eriksson at the police's regional command center to SVT.
He says to Expressen that "the initial value was drug crime and then weapons and a suspected dangerous object were found".
The crime classification is weapons offences, drug offenses and offenses against the Act on Flammable and Explosive Goods.