SAN FRANCISCO (CBS SF) — Two stolen ancient sacred lintels donated to the San Francisco Asian Art Museum by former International Olympic Committee head Avery Brundage were returned this week to the government of Thailand, federal authorities revealed Friday.

The federal government sued San Francisco back in October of last year over the artifacts, which Thailand officials said were stolen.

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The city obtained the two lintels, which are two 1,500-pound hand-carved decorative relics, over 50 years ago and they’ve been in San Francisco’s Asian Art Museum since the museum’s opening in 1966. One lintel is from Nong Hong Temple and dates to 1000-1080 AD and the other is from Khao Lon Temple and dates to 975-1025 AD.

Federal and city officials reached a settlement of a lawsuit over ownership of the artifacts in February 2021.

The return of the lentils to Thailand marked the culmination of a three-year probe by HSI Bangkok, HSI San Francisco, and subsequent prosecution by the U.S. Attorney.

“Today, with immense honor and respect, we are reuniting these cultural treasures with their rightful owners – the Kingdom and people of Thailand.” said Tatum King, Special Agent in Charge for HSI San Francisco. “The theft and trafficking of another country’s priceless and irreplaceable national treasures are a global concern that requires close collaboration between nations.”

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In 2017, Homeland Security investigators received information from Thai officials concerning stolen lintels from two ancient Khmer era sanctuaries sometime during the late 1950s or early 1960s.

Painstaking investigation revealed suspicious activities related to the acquisition of the ancient art and that the lintels were the property of the Kingdom of Thailand at the time they were removed from their ancient structures.

Since 2007, Homeland Security has repatriated more than 15,000 objects to over 40 countries and institutions. In November 2014, HSI returned more than 500 artifacts to Thailand, including pottery, bronze ornaments and tools.

As recently as April 2021, HSI New York worked with the Manhattan District Attorney’s Office to return more than a dozen artifacts to the government of Thailand, including a bronze standing Buddha.

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Members of the public who have information about the illicit distribution of cultural property, as well as the illegal trafficking of artwork, are urged to call the toll-free tip line at 1-866-347-2423 or to complete the online tip form.