After authorities determined a rare dinosaur skull he bought at an auction for $276,000 was stolen, Nicolas Cage has voluntarily handed over the artifact to be returned to the Mongolian government.

A civil forfeiture complaint filed on Dec. 16 by U.S. attorney Preet Bharara's office in Manhattan has resulted in authorities taking possession of the Tyrannosaurus bataar skull bought by the actor in order to return it to Mongolia. Cage's publicist confirmed to Reuters that the "National Treasure" star was the owner of the skull and that he has not been accused of any crime.

Actor Nicolas Cage attends Paper Street Films' Screening Of "The Runner" at TCL Chinese 6 Theatres on August 5 in Hollywood, California. Jason Kempin / Getty Images

Cage, who also collects rare cars and vintage comic books, bought the skull in 2007 from the Bevery Hills gallery I.M. Chait, which included a certificate of authenticity. However, the Department of Homeland Security contacted Cage in July 2014 while an investigation was underway over whether it was illegally taken from Mongolia, Cage's publicist told Reuters.

The skull is from a dinosaur that lived about 70 million years ago and is considered a relative of the famed Tyrannosaurus rex. The dinosaur is indigenous to the Gobi Desert in Mongolia. Since 2012, Bharara's office has been responsible for the return of numerous fossils to Mongolia, including three full Tyrannosaurus bataar skeletons.

“Cultural artifacts such as this Bataar Skull represent a part of Mongolian national cultural heritage,” Glenn Sorge, a special agent with Mr. Bharara’s office, said in a statement. “It belongs to the people of Mongolia. These priceless antiquities are not souvenirs to be sold to private collectors or hobbyists.”

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