CHICAGO (CBS)As a downtown firehouse observed the 10th anniversary of the 9/11 terrorist attacks Sunday, firefighters there were still wondering what happened to a link between Chicago and Ground Zero that disappeared a year ago.

As WBBM Newsradio’s Steve Miller reports, like other fire stations in Chicago, Engine 13 at Columbus Drive and South Water Street sent firefighters to New York City to volunteer in the days after Sept. 11, 2001.

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LISTEN: WBBM Newsradio’s Steve Miller reports

They brought back something – they put in a shrine to those who died.

“A piece of the World Trade Center, a piece of the concrete from the building, and a fire safety drill paper that must have been found on the street,” said firefighter-paramedic Steve Horner. “And it was tattered.”

The shrine hung on the wall until about a year ago, when Horner says one day, the objects all disappeared.

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“One day it was in the acrylic case, and the next day it was gone,” he said.

It was stolen, Horner says, most likely by a visitor who wandered in.

“It was pretty nice to have it up there, he said, “and now it’s just gone.”

Horner says nobody knows for sure, but the engine company’s ties to 9/11 – and the remembrance of their work at Ground Zero – could be on eBay.

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“It’s kind of low,” he said. “It’s low.”