"We have not received any reports of personal injuries so far," says police spokesperson Ola Österling.
The police operation is ongoing throughout northern Stockholm, according to Österling. A criminal investigation has been opened into damage to public property and a serious violation of the Explosives and Flammable Goods Act. Bomb disposal experts are on their way to the scene.
The gate in question reportedly sustained only limited damage.
There is no information that anyone has been detained in connection with the case.
The police received the alarm at 10:27 p.m. after "numerous" emergency calls, according to Ola Österling.
