“When the patrol took a closer look they discovered that it was primed with what we presume to be plastic explosives,” said police spokesman Per Ahlström.
“It look likes a pretty big charge, one to one and a half kilos. So there would definitely have been a major bang if their plan had succeeded” he added.
Police have cordoned off an area around the bank with a radius of 150 metres.
There have not yet been any indications regarding who might be behind the planned attack.