US federal investigators are seeking to confiscate an ancient artefact from the Museum of the Bible and return it to its country of origin.

Prosecutors with the Department of Justice say that the precious tablet, which is inscribed with a portion of the Gilgamesh ⁠— an ancient poem widely regarded as the oldest surviving great work of literature ⁠— was bought by Christian-owned craft store Hobby Lobby for a sum of $1.6 million. Hobby Lobby's president, Steve Green, founded the Washington D.C.- based museum and serves as the Chairman of the Board. 

According to a statement by the DOJ, the Gilgamesh Dream Tablet, "originated in the area of modern-day Iraq and entered the United States contrary to federal law." Hobby Lobby is now suing the auction house, Christie's, from which it bought the prized possession, arguing that they breached the terms of their sales contract.

According to DOJ officials, both the museum and Hobby Lobby requested information from the auction house regarding the tablet's origins. However, the auctioneer allegedly failed to share that information and proceeded to lie by claiming that the antiquities dealer had offered trustworthy confirmation with regards to the artefact's place of origin. 

The tablet was seized from the Museum of the Bible by law enforcement agents in September of last year, before filing a civil complaint to forfeit the rare piece on Monday.

In a statement, US Attorney Richard Donoghue said: "Whenever looted cultural property is found in this country, the United States government will do all it can to preserve heritage by returning such artefacts where they belong." 

He added: "In this case, a major auction house failed to meet its obligations by minimizing its concerns that the provenance of an important Iraqi artefact was fabricated, and withheld from the buyer information that undermined the provenance's reliability."

The DOJ said that the Museum of the Bible is cooperating with the investigation, with a spokeswoman for the attraction noting that the museum "supports the Department of Homeland Security's efforts to return this Gilgamesh fragment to Iraq."

Spokesperson Charlotte Clay told CNN: "Before displaying the item in 2017, we informed the Embassy of Iraq that we had the item in our possession but extensive research would be required to establish provenance.

"We have continued these private discussions with Iraqi officials. We announced previously that we would be assisting in the return of items to Iraq and Egypt, and we have cooperated with Homeland Security on all of these matters."

A Christie's spokesperson said in a statement: "..this filing is linked to new information that has come to light regarding an unidentified dealer's admission to government authorities that he illegally imported this item, then falsified documents over a decade ago in order to perpetrate an illegal sale and exploit the legitimate market for ancient art.

"Now that we are informed of this illicit activity pre-dating Christie's involvement, we are reviewing all representations made to us by prior owners and will reserve our rights in this matter

"Any suggestion that Christie's had knowledge of the original fraud or illegal importation is unsubstantiated."