An unattended bag, which initially tested positive for explosive materials, shut down ticketing counters at the Minneapolis-St. Paul International Airport for an hour and a half this afternoon.

The bag was left at a United Airlines scale. Transportation Security Administration agents swabbed it shortly after noon. The swab tested positive for explosives, so the airport shut down the northern half of the Terminal 1 ticket counters.

The city of Bloomington's bomb squad was called in and found that there were no explosives inside the bag.

Airport spokesperson Melissa Scovronski said,"We do not know why it tested positive, obviously there were no explosives in there. So we are looking into why that happened, who left it there and why they left it there."

The scene was cleared at about 2 p.m. and the airport resumed normal operations. The scare led to delays at ticket counters and at the airport drop-off and pick-up locations.