The packages that made their way from Israel and the United Arab Emirates to retail outlets owned by Hobby Lobby, the seller of arts and craft supplies, were clearly marked as tile samples.

But according to a civil complaint filed on Wednesday by federal prosecutors in Brooklyn, they held something far rarer and more valuable: ancient clay cuneiform tablets that had been smuggled into the United States from Iraq.

Prosecutors said in the complaint that Hobby Lobby, whose evangelical Christian owners have long maintained an interest in the biblical Middle East, began in 2009 to assemble a collection of cultural artifacts from the Fertile Crescent. The company went so far as to send its president and an antiquities consultant to the United Arab Emirates to inspect a large number of rare cuneiform tablets — traditional clay slabs with wedge-shaped writing that originated in Mesopotamia thousands of years ago.

In 2010, as a deal for the tablets was being struck, an expert on cultural property law who had been hired by Hobby Lobby warned company executives that the artifacts might have been looted from historical sites in Iraq, and that failing to determine their heritage could break the law.