Turns out Metro’s “See Something, Say Something” campaign might be working.

A rider reported seeing a suspicious package at Metro Center on the tracks on the Glenmont-bound side. Metro Transit Police’s bomb squad was called in, but it turns out it was simply a trash bag.

Metro’s chief spokesman Dan Stessel said trains were held for “less than five minutes” until the third rail power could be brought down and police could get the bag off the tracks.

Just before noon, he said, trains had resumed normal operating service and plans to call in buses were canceled.

“It was deemed harmless,” he said.