The United States has returned 11 cultural artifacts to the government of Nigeria.

Authorities said on Thursday that French customs officials had tipped off the U.S. in April 2010 about a shipment headed to New York’s Kennedy airport. The 10 Nok (nahk) statues and a carved tusk were seized from a Manhattan gallery owner, and an investigation determined they were bona fide antiquities. The artifacts are to be displayed in Nigeria’s national museum. Nok statues are about 2,000 to 2,500 years old, among the oldest sculptures in West Africa. They were first unearthed in 1943 at a tin mine near the village of Nok in central Nigeria. Homeland Security investigators (HSI) say two Nok statues and a carved ivory tusk were previously seized at Chicago O’Hare international airport.

After investigation with assistance from French authorities, the Louvre in Paris, Interpol and the International Council of Museums, HSI special agents determined what the statues were, and not just handicrafts and personal effects as disclosed in the importation documents provided to the authorities.

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