PORTLAND – A passenger’s flute tucked inside a homemade container triggered the Portland International Jetport’s evacuation Tuesday because screeners thought the package had the elements of a potential bomb.

Eight flights were affected and more than 300 passengers evacuated while bomb technicians investigated.

The state’s busiest airport reopened in less than two hours. The passenger was allowed to board his flight after being questioned, but without his flute, which he left behind in the trunk of his car.

A security screener at one of the X-ray machines noticed the item in a carry-on suitcase shortly before 6 a.m.

What looked like an explosive device was actually an electric flute, with wires and a rectangular battery, all encased in a homemade PVC pipe container constructed by the passenger to protect the instrument.

“It was similar to what they see in their training as a pipe bomb,” airport security director Robert Dyer said, “but he could not assess at that point that it was an actual device.”

Portland police responded within minutes and a bomb disposal squad removed the item and e-mailed pictures to experts in Washington.

Departing planes backed away from their gates and incoming planes stayed on the tarmac after landing. Passengers and airport staff, who were evacuated to nearby car-rental offices, returned to the terminal at 7:45 a.m.

Eight departing flights were affected. Six were delayed and one was canceled, and six passengers missed a flight that left without them.