What was a suspicious package discovered at Boeing’s Auburn parts plant late Friday afternoon turned out to be harmless, authorities said.

As many as 90 workers were evacuated from the building, and a bomb squad was called in to investigate. The workers returned to the building around 9 p.m.

A suspicious package wrapped in duct tape was found in a restroom in the building. However, the package was not an explosive.

The bomb threat came within hours of Boeing machinists going on strike.