An Iranian cancer researcher who was detained at Boston's Logan International Airport has been sent back to his home country.
U.S. Customs and Border Patrol spokeswoman Stephanie Malin says Mohsen Dehnavi and his family were put on a return flight shortly after 9 p.m. Tuesday.
Dehnavi was to have started work at Boston Children's Hospital.
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The hospital says he was prevented from entering the country with his wife and three young children despite holding a J-1 visa for visiting scholars. They arrived at the airport Monday.
Malin says the family's detention was for "reasons unrelated" to President Donald Trump's executive order on travelers from six predominantly Muslim countries. She says the stop was based on information discovered during the agency's review.
But Malin noted that visa applicants "bear the burden of proof" to meet all requirements and can be denied entry for a range of reasons, including health-related issues, criminality or security concerns.
The Supreme Court recently ruled the Trump administration could largely enforce its temporary ban on travelers from Iran, Libya, Somalia, Sudan, Syria and Yemen. But the court said the ban can't block people with a "credible claim of a bona fide relationship with a person or entity in the United States."
Some advocacy groups, including the American Civil Liberties Union and the National Iranian American Council, suggested the detention might be a violation of the Supreme Court order.
"The family is very worried," said Shayan Modarres, a lawyer for the D.C.-based council, which has been in contact with the family. "If it is a minor paperwork issue, then something needs to be told to the family so they can resolve it."
At the very least, the incident shows how the administration's political priorities are leading to "overzealous enforcement" of immigration laws, said Gregory Romanovsky, chair of the New England chapter of the American Immigration Lawyer's Association.
"Exercising discretion is not what they're comfortable doing anymore, especially if they're dealing with someone from one of the six banned countries," he said of local customs officials. "The travel ban and the whole anti-immigrant mood coming from the very top of this administration certainly affects their ability."
Boston Mayor Marty Walsh, a Democrat, told reporters he was waiting to hear more about the Dehnavis' circumstances, but also suggested the case was an example of concerns with the travel ban.