Airport X-ray screeners mistook a metal cylinder in a man's luggage for a pipe bomb, prompting a shutdown Monday of three concourses at Portland International Airport (search), officials said.

The man when questioned could not identify the object because he didn't know he was carrying it, said Jennifer Marty, a spokeswoman for the federal Transportation Security Administration (search).

"His wife had put the package in his carry-on," Marty said.

She said the metal instrument is used in baptisms: "It's for christening a baby. It's hollow, like a pipe. It has ends that remove on both ends. There was some sort of electric music box in the package, too. Wires, that kind of thing."

Both were intended as gifts for another family, Marty said.

The man, who was traveling on a Southwest Airlines (search) flight to Los Angeles via Oakland, was eventually allowed to board. Authorities did not release his name.

Officials also declined to comment on the man's religion.

The security checkpoint for the concourses was closed for 90 minutes as a federal bomb squad checked the package, said Elisa Dozono, a Port of Portland spokeswoman.