WASHINGTON – The 22-year-old philosophy student from China did not expect any problems after his 29-hour flight arrived at a Texas airport this month as he was on his way to study at the University of Houston.

His paperwork was in order. He was going to study humanities — not a tech field that might raise suspicions. He had a full scholarship from the U.S. school and had previously spent a semester at Cornell University for an exchange program with no issues.

But the student, who asked to be identified only by his family name, Gu, because of the political sensitivities of the matter, was stopped, interrogated and 36 hours later, put on a plane back to China.

He also was banned from coming back for five years, abruptly halting his dream for an academic career in the United States.

“There is no opportunity for the life I had expected,” Gu said.

He is one of an unknown number of Chinese students with permission to enter the United States who have been sent back to China or faced intense questioning after their arrival, drawing strong protests from Beijing and showing the uncertainty from President Donald Trump’s shifting policies.

His administration has quickly pivoted from a plan to revoke visas for Chinese students to Trump himself saying he would welcome hundreds of thousands of them, partly to help keep some American schools afloat.

The US has put restrictions on Chinese students

Even so, some officials and lawmakers have expressed suspicions about Chinese students, especially those who study advanced technologies such as quantum computing and artificial intelligence, and their possible links to the Chinese government and military. Some lawmakers want to ban Chinese students altogether.

There’s no immediate data available on how many Chinese students with valid visas have been interrogated and repatriated from U.S. airports in recent weeks. U.S. Customs and Border Protection did not respond to a request for that data or for comment on Chinese students being questioned or sent back.

In recent days, Trump said he told Chinese President Xi Jinping that “we’re honored to have their students here.” But he also added, “Now, with that, we check and we’re careful, we see who is there.”

The Chinese Embassy said it has received reports involving more than 10 Chinese students and scholars being interrogated, harassed and repatriated when entering the U.S.

“The U.S. side has frequently carried out discriminatory, politically driven and selective law enforcement against Chinese students and scholars, inflicting physical and mental harm, financial losses, and disruptions to their careers,” the Chinese Embassy said in a statement.

They were repatriated under the pretext of “so-called ‘visa issues’ or ‘might endanger U.S. national security,’” the embassy said.

The students and scholars were taken into small rooms for extended interrogation, repeatedly questioned on issues unrelated to their academic work, and forced to wait long hours in cold rooms without blankets or quilts, the embassy said. Some relied on aluminum foil to keep warm, and some were detained for more than 80 hours, it said.

Such acts by the U.S. side “run counter to the statements” made by Trump, the embassy said, accusing some U.S. departments and law enforcement personnel of not “faithfully acting on the president’s commitment.” The White House didn’t immediately respond to a request for comment.

One Chinese student had no concerns as he headed to the US

Gu told AP that he liked his Cornell experience so much that he applied for a master’s program to study philosophy in the U.S.

Despite reports of stricter policies by the Trump administration, Gu said he wasn’t too worried, not even when he was first stopped and taken to a room for questioning by a customs officer after landing at George Bush Intercontinental Airport in Houston. His belongings were searched, and his electronics were taken away, he said.

After the officer went through the devices, he started interrogating Gu, focusing on his ties to the Chinese Communist Party, Gu said.

He said his parents are party members, but he has never joined, though he — like nearly all Chinese teens and young people — is a member of the party’s youth arm, the Communist Youth League.

The customs officer also grilled him on his connections to the governmental China Scholarship Council, which popped up in his chat history. Gu said it came up in his chats with his schoolmates, but he did not receive money from the Chinese government.

Three rounds of interrogation lasted 10 hours, before Gu was told he was to be deported. No specific reason was given, he said, and the removal paperwork he provided to AP indicated inadequate documentation.

By then, he had hardly slept for 40 hours. The waiting room where he was kept was lit around the clock, its room temperature set low.

“I was so nervous I was shaking, due to both being freezing cold and also the nerves,” Gu said. “So many things were going through my head now that I was being deported. What should I do in the future?”

It would be another day before he was put on a flight. Now, Gu is considering appealing the decision, but that might take years and cost thousands of dollars.