The Utah Bureau of Land Management said on Saturday it had received “credible reports” that the object was removed “by an unknown party” on Friday.
The office “has not removed the structure which is considered private property,” he said in a statement.
“We do not investigate crimes involving private property that are handled by the local sheriff’s office.”
The shiny triangular pillar, which protruded about 3.7 m (12 feet) from the red rocks of southern Utah, was spotted on November 18 by local officials counting bighorn sheep in the air.
After landing their helicopter to investigate, crew members from the Utah Department of Public Safety found “a metal monolith set in the ground” but “no clear indication of who might have put the monolith in it.” .
The mysterious structure has attracted media attention and sparked theories that it was the work of aliens.
Many social media users noted the object’s similarity to strange alien monoliths that trigger huge strides in human progress in Stanley Kubrick’s 2001 classic sci-fi film: A Space Odyssey.
Meanwhile, some observers have pointed to the object’s resemblance to the avant-garde work of John McCracken, an American artist who lived for a time in neighboring New Mexico and died in 2011.
His son, Patrick McCracken, recently told the New York Times that his father told him in 2002 that he “would like to leave his works in remote places to be discovered later.”
Bret Hutchings, the pilot who flew over the monolith, speculated that it had been planted by “a new wave artist”.
He said it was “about the strangest thing I have come across out there in all my years of flying.” ”
“We were kind of joking that if one of us suddenly disappears, then the rest of us are racing,” he told local news channel KSLTV.
Although authorities have refused to release the location of the object over fears that hordes of curious tourists will flock to the remote nature, some explorers have been able to locate it.
Instagram user David Surber said he traveled to the monolith using contact details posted on Reddit.
“Apparently the monolith is gone,” he later posted.
“Nature has returned to its natural state, I guess. Something positive for people to come together in 2020. ”