The United States’ Customs and Border Protection (CBP) agency is facing backlash after it was revealed the agency had refused entry to an Iranian student with a valid visa and forced him on a flight back home, despite a judge issuing an emergency stay of removal, Newsweek reported on Wednesday.

Shahab Dehghani, 24, who was planning to study economics at Northeastern University, arrived in Boston on Sunday night with a valid student visa but was held at the airport overnight for questioning and put back on a plane to Iran the next evening.

Susan Church, an attorney assisting Dehghani, said he had been granted an emergency stay of removal from Massachusetts District Court Judge Allison D. Burroughs while Dehghani was still at the Boston airport.

The order demanded that Dehghani’s removal be stayed for 48 hours or until further order of the court, while a hearing for the 24-year-old was arranged for Tuesday morning.

In video published online, protesters who had raced to the airport to demand that the student be allowed to enter the country could be seen cheering after they heard the stay of removal had been granted.

However, they were later dismayed to learn that Dehghani had been put on a plane back home without their knowledge, despite the judge’s emergency order.

In a statement sent to CNN, CBP said it was “unaware of the issuance of any court order barring the removal of the subject from the United States” when Dehghani had boarded the flight.

The American Civil Liberties Union (ACLU) of Massachusetts has claimed that since August 2019, at least 10 students have been sent back to Iran upon arriving at U.S. airports. Seven of those students, the ACLU branch said, had flown into Logan airport. Newsweek has contacted CBP for more information.

In a statement shared with Newsweek, Carol Rose, the executive director at the ACLU of Massachusetts, said: “In America, nobody is above the law—including Customs and Border Protection officials.”

“Given the Trump administration’s xenophobic policies and CBP's troubling practice at Logan Airport of sending students with valid visas back to Iran, it is shameful that the government defied a federal court order and deported Shahab without due process,” Rose said, adding: “We are looking at all options to hold CBP accountable for wrongfully deporting Iranians and other students who hold valid visas.”

In a statement shared with Newsweek, Cornell University Law School professor Stephen Yale-Loehr said he was disturbed to hear not only about Dehghani’s story, but also of reports of dozens of Iranian Americans claiming to have been detained and questioned at a border crossing in Washington state recently.

Yale-Loehr said he had heard of multiple cases of Iranian students being turned away at airports since August, amid tensions between the U.S. and Iran. “And earlier this month, many U.S. citizens of Iranian descent were questioned for hours trying to return to the United States from Canada,” the professor said.

It is still unclear why Dehghani was turned away at Boston airport.

If the 24-year-old did have a visa, Yale-Loehr suggested Americans should be asking questions as to why he was denied entry into the U.S.

“The U.S. State Department already thoroughly vets all applicants before issuing visas,” the professor said. “There is no need for immigration inspectors to deny entry to people with proper visas simply because they are from Iran. These actions needlessly increase tensions with Iran.”

While there is no evidence that CBP denied Dehghani entry because he is Iranian, the recent incidents at U.S. ports of entry come at a time of heightened tensions with Iran following the U.S. assassination of General Qassem Soleimani and Iran’s missile attack on bases in Iraq in response to the killing.