The cryptic metal structure which has captivated imaginations since it was discovered in the Utah desert last week, has been stolen, according to disappointed pilgrims who traveled hundreds of miles to see it.

The Bureau of Land Management in Utah has confirmed a series of “credible reports” that the monolith is no more, saying that the structure was taken by an unknown “person or group” on Friday night.

BLM did not remove the structure which is considered private property.

Officials said they have no clue who removed the obelisk — and are still scratching their heads over who installed it there in the first place, possibly years ago.

“We have received credible reports that the illegally installed structure, referred to as the “monolith” has been removed by an unknown party. The BLM did not remove the structure which is considered private property…” More:

When it was discovered last week, the strange object was dubbed the ‘monolith’, despite being metallic and hollow, in homage to Stanley Kubrick’s ‘2001: A Space Odyssey’. While more popular — and unimaginative — theories claim that the structure is either a marketing gimmick, a publicity stunt, an art installation or a prank, many online have conjured up more elaborate and otherworldly ideas as to its purpose.

READ MORE: ‘Alien super weapon? Xbox prototype?’ Internet sleuths uncover coordinates of ‘Utah monolith’ as netizens debate origin & purpose

But backpackers and thrill hunters, who flocked into the area immediately after its location was pinpointed by online sleuths, believe the artefact was stolen rather than taken by rightful owners, be they terrestrial or extraterrestrial.

A post shared by Sierra Van Meter (@sierra_rosevm)

Riccardo Marino and Sierra Van Meter, a pair of hikers who claim to be the first to arrive at the scene possibly just minutes after the obelisk vanished, said that “all that was left in its place was a message written in the dirt that said ‘bye b*tch’ with a fresh pee stain right next to it.”

We arrived at the location to see nothing but the foul markings left and we realized we must have been the first people to see it removed.

In a bid to pay ‘space oddity’ its due respect, they created a “rendition of the monolith returning back to space” instead of being taken by petty thieves.

In a video blog about the incident, they also recall how on their way to the scene they heard voices in the dark and saw a suspicious truck “hauling a large object strapped down in the bed with the hatch open.”

Yep. It’s gone.?Courtesy: Kelsea Dockham | Canyon State Overland

In the meantime, someone has since installed a small cairn marking the spot where the mysterious structure — a 3-meter-tall, not-so-monolithic pillar with triangular cross-section — once stood, according to a series of photos shared by another hiker and camper, Richard Michaelson.

A post shared by Richard Michaelson (@code_blue_ut)

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