AUBURN, Wash. - Officials declared the Boeing Co.'s Auburn plants safe again after a suspicious device found inside a bathroom triggered alarm Friday afternoon.

About 90 people were evacuated from the plant after a device was found on the premises, said Boeing spokesman Jim Proulx.

A bomb squad inspected the device, which consisted of a metal pipe filled with drill bits and rivets, and concluded it did not pose a threat. Crews also searched the premise and found no other suspicious items.

The evacuation order came less than two hours after Boeing's machinists announced they would go on strike at 12:01 a.m. Saturday after last-ditch efforts failed to negotiate a contract.

The 2.1 million-square-foot Boeing Auburn plant is reportedly the largest airplane parts plant in the world, making and storing more than 200,000 parts for Boeing commercial jetliners.