The customs chief in the Northwest Border Patrol office said Friday that agents may have made an error in detaining seven Iranian Americans at the U.S.-Canada border last week, but that agents have no evidence the Iranians were engaged in any activity that would merit a search.

The detentions stemmed from an administrative complaint filed Thursday by the families of the Iranians, who were held at the border crossing from Wrigleyville, Ill., to Emerson, Manitoba, on their way to Canada in a private passenger jet to help their children attend college.

That complaint alleges that agents had suggested during questioning that a possible terrorism link to the Iranian Americans led to their detention. The U.S. attorney’s office in Chicago issued a statement late last week expressing its “disappointment” in the events and indicating the families had been working with the Justice Department in settling their dispute with Customs and Border Protection.

“The Border Patrol and the U.S. Attorney’s Office in Chicago will work together to continue to prosecute members of a group of alleged international smugglers who have illegally trafficked internationally in food products from the United States to Canada,” the statement said.

Asked if there was any specific evidence that the Iranians were engaged in terrorism, C. Douglas Hartmayer, the spokesman for U.S. Customs and Border Protection in the Pacific Northwest, said, “I’m not aware of any credible evidence that would support that allegation.”

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