They were turned back from flights to the United States in Tehran and in the major transfer hubs of Istanbul and Dubai. Some of those who arrived in the United States after midnight, when the decree went into effect, were held or deported, rights groups and airline representatives said.
No one, not passengers, airline representatives or even United States border control officials, seemed to know how to interpret the executive order that went into effect at midnight on Friday. Under the new policy, refugees, immigrants and almost anyone from seven countries deemed to be hotbeds of terrorism are banned from the United States for 90 days, pending a review of policies.
Officials are just interpreting the directive by themselves, said one representative for an international airline who was based in Tehran. He said the airline did not know if Iranians could fly to the United States or not.
On Saturday, three international airlines shuttling passengers between Iran and the United States — Emirates, Lufthansa and Qatar Airways — had stopped allowing Iranians with visas or even permanent residence cards to board their planes. The Qatar Airways office in Tehran confirmed that all Iranian passengers without United States passports were stopped from flying to the United States on Friday evening and sent back to Iran.
In Istanbul, during a stopover on Saturday, passengers reported that security officers had entered a plane after everybody boarded and ordered a young Iranian woman and her family to leave the aircraft.
Holders of green cards, which confer the right to live and work indefinitely in the United States, received conflicting information about whether or not they would be permitted to return to the United States. But on Saturday, the Department of Homeland Security clarified the executive order, saying it applied even to permanent residents from the seven Muslim-majority countries named in the ban: Iran, Iraq, Libya, Somalia, Sudan, Syria and Yemen.
“It will bar green card holders,” Gillian Christensen, the Department of Homeland Security’s acting spokeswoman, told Reuters.
Many were blindsided by the decree while on vacation in Iran. “How do I get back home now?” said Daria Zeynalia, a green card holder who was visiting family in Iran. He had rented a house and leased a car and would be eligible for citizenship in November. “What about my job? If I can’t go back soon, I’ll lose everything,” he said.
It is unclear how many Iranians have green cards, but experts say the number runs into the hundreds of thousands.
In an online survey tracking entry challenges, two out of 112 passengers holding green cards said they were not allowed into the United States, but the reasons were unclear. Card holders can be barred, for instance, if they owe back taxes.
Others spent years preparing to study in the United States only to see their plans abruptly thwarted on Friday. About 4,000 Iranians are granted study visas to attend American universities each year, often after a long and complicated process that can take years.
Shadi Heidarifar, a philosophy student just admitted to New York University, said in a message on Twitter that she had spent three years trying to apply to universities in the United States.
“I had to work to save money, gather documents. The application fees were so expensive that a whole family could live for a month” on them, Ms. Heidarifar wrote. When she was accepted recently, she was over the moon. “But now my entire future is destroyed in one second.”