A bomb scare that shut a terminal at Minneapolis-St. Paul International Airport for 90 minutes on Friday morning was caused by a passenger carrying what he said was a water filtration system in his checked baggage, an official said.
Police questioned and released the man without charges after the materials were determined to not be explosive, airport spokesman Patrick Hogan said. He declined to identify the man because he was not charged.
"The questionable items in the bag were two PVC pipes capped at both ends filled with a granular material," Hogan said. "There were also a number of wires in the bag that were not connected to the pipes."
"The individual claimed it was a device for water filtration," Hogan said.
Witness Bev Aho of Eden Prairie was at the Humphrey terminal when she and other travelers were evacuated by authorities around 5:15 a.m. as she was entering the terminal for a flight.
Metropolitan Airports Commission spokesperson Melissa Scovronski tells KARE 11 that the suspicious bag set off an alarm during security pre-screening. Airport Security could not resolve the situation so a decision was made to call in the Bloomington Police Bomb Squad.
Passengers who were already inside the pre-screening area were allowed to stay in the terminal, but anyone arriving after the discovery of the package was diverted to the parking ramp across the street from the Humphrey terminal.
Terminal 2 serves Southwest Airlines, AirTran, Sun Country and Iceland Air, Hogan said. The larger Terminal 1 and airport runways were not affected by the incident, he said.
At this point it is uncertain what impact the incident will have on flights in terms of delays and potential cancellations. Passengers are urged to call their airlines before heading to the airport.
Metro Transit reports that the activity has not affected light rail service to the airport.
Reuters and NBC-affiliate KARE 11 contributed to this report.
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