She told parliament that the Swedish Agency for Non-Proliferation and Export Controls (ISP) had informed her that the arms came from India.
"And as a result I asked ISP to request clarification from the Indian authorities," Bjorling said.
Pictures taken by a Myanmar freelance photographer and published in the Swedish media this week show a Carl Gustaf M3 anti-tank rifle and ammunition left behind by Myanmar government soldiers.
The weapon's serial number is clearly visible in one of the photographs.
The European Union has had a weapons embargo against Myanmar since 1996.
On Wednesday, an ISP spokeswoman said it was "relatively unusual" for Swedish weapons to end up in the hands of third parties.