The bomb squad was on its way to the scene at 5 a.m.
"We don't know exactly what went off yet. The National Bomb Squad has been involved," says Joar Källman, commander at the police command center.
According to Källman, the property has not suffered any major damage and there are no reports of personal injuries. However, a fire has broken out at the site.
Police would not comment on whether any suspects or arrests have been made.
It is an isolated incident and poses no danger to the public, says Joar Källman.
The alarm came at 4 a.m. on Sunday.
