A pressure cooker found in a parking spot at the Bangor Walmart on Wednesday caused the store to temporarily close as the Bangor police bomb squad investigated and determined it was not a bomb. The bomb squad removed the cover from the pressure cooker. Credit: Courtesy of Bangor Police Department

A pressure cooker in a parking spot shut down the Bangor Walmart for about an hour on April 7, then 10 days later in an adjacent parking lot, a duffel bag triggered a similar response. Neither suspicious item ultimately posed a threat, but their discovery prompted the Bangor police to shut down the parking areas each time and call in their department’s bomb squad.

The Bangor Police Department receives calls often about unattended or discarded items that some consider suspicious. But in the two cases at busy shopping centers on Stillwater Avenue, the circumstances were suspicious enough to call out the bomb squad, said Detective Sgt. Tim Shaw, the department’s bomb squad commander.

Bangor police deploy the bomb squad only when the circumstances are suspicious and the police chief — or sometimes the deputy chief — approves the deployment, Shaw said.

Authorities are already more suspicious of pressure cookers than other items due to their use in past attacks, including the Boston Marathon bombing in 2013. But the circumstances under which the device ended up in a Walmart parking spot made officers believe it was important to call in the bomb squad, Shaw said.

Somebody had driven into the Walmart parking lot and placed the pressure cooker, an Instant Pot, on the ground before leaving, he said.

“Taking any of those factors alone probably wouldn’t be suspicious,” Shaw said. “But when you put them all together, it makes it suspicious.”

The second incident was similar. Someone pulled into the parking lot of the Stillwater Avenue plaza containing AT&T, Mattress Firm and TD Bank and placed a duffel bag down before leaving, Shaw said.

The proximity of that shopping plaza to the adjacent Walmart parking lot where the pressure cooker was discovered days earlier further increased suspicion of the duffle bag, Shaw said. Police had also received a call about the man who placed the bag down on the ground, he said.

Numerous factors can make an abandoned item a potential threat, including if the item is unexpected or out of place, or if it is directed toward someone who has received threats in the past, said Jimmie Oxley, a chemistry professor and explosives expert at the University of Rhode Island.

Oxley, who has worked with authorities on bomb squad responses in the past, said police departments had begun to take suspicious devices much more seriously in the aftermath of the Sept. 11, terrorist attacks. Police departments are generally better being safe than sorry, she said.

“Young people used to get away with a lot more than they do now. When they were fooling around and blowing up mailboxes, people did take it as a prank,” Oxley said. “Now, our mindset has changed. This is domestic terrorism.”

Police departments also have an incentive to use their bomb squad equipment because it requires specific funding, Oxley said.

The two recent abandoned items are far from the first to which the Bangor Police Department’s bomb squad has responded.

In January 2020, the police sent a bomb squad to a man’s home after he allegedly showed officers a gas container shortly after threatening to burn down a neighbor’s home. And in 2019, the bomb squad responded after a man dropped off two suspicious packages at the Penobscot County Jail. The packages did not pose a threat.

Last month in Livermore Falls, a bomb squad disarmed explosive devices left in a home where a man held three people hostage.