Diver thieves have stolen the sunken bell from the Costa Concordia wreckage, evading 24-hour surveillance by the Italian coastguard and police.

Engraved with the ship's name and the year it was launched, 2006, the iconic brass bell was resting at a depth of 26 feet. It once hung on the bridge of the doomed liner.

Weighing more than 22 pounds, the gleaming bell was secured with heavy duty bolts, meaning it would likely take more than one person to remove it — and get it onto shore unnoticed.

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According to Francesco Verusio, the prosecutor for the investigation of the Costa Concordia shipwreck, the bell disappeared around two weeks ago.

Investigators tried to keep the news quiet, he said. But rumors began to spread among locals about the baffling disappearance.

The location of the ship, which struck a rock and ran aground the Tuscan coast of Giglio island on Jan. 13, killing 25 people and leaving seven missing, is considered a crime scene and is continuosly guarded by the Italian coast guard and police.

Only authorized divers and boats, as well as the team involved in pumping the fuel from the ship's tankers are allowed to approach the wreck.

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The thieves were also able to bypass the complex laser systems which measure millimetric shifts in the shipwreck. Indeed, the Concordia lies half-submerged precariously balancing on two rocks.

"I can only guess that someone took it as a sort of morbid memento," Giglio mayor Sergio Ortelli told Reuters.

A very unique item, the bell was supposed to remain on the island as a historic monument of the tragedy.

"In my mind, the missing bell is of no importance. We have the ship's statue of the Madonna in our church, and that for us has much more symbolic meaning," Ortelli said.

Photo: The bell of the Costa Concordia. Credit: Italian Carabinieri.