Federal prosecutors trying to seize a multimillion-dollar 10th-century Cambodian statue from Sotheby’s have accused the auctioneers of colluding with the item’s owner to hide information that it was stolen from a temple in 1972, according to papers filed in United States District Court in Manhattan.

Prosecutors say that in 2010, when the statue was being imported into the United States, the owner submitted an inaccurate affidavit to American customs officials, at Sotheby’s request, stating the statue was “not cultural property” belonging to a religious site.

The government contended in its filing on Friday that both parties knew the statue, a mythic Hindu warrior known as Duryodhanna, valued at up to $3 million, was stolen when they agreed to ship it from Belgium to New York. The government says it can prove that the statue in fact came from a Khmer Dynasty temple, Prasat Chen, part of a vast and ancient complex called Koh Ker....