Fangzhou Jiang, a graduate student at the Harvard Kennedy School, had quite an emotional roller-coaster ride between the Trump administration's barring of all international students from attending Harvard University on Thursday and a court ruling to halt the decision the next day.

Homeland Security Secretary Kristi Noem ordered her department to terminate Harvard University's Student and Exchange Visitor Program certification, claiming that "Harvard's leadership has created an unsafe campus environment by permitting anti-American, pro-terrorist agitators to harass and physically assault individuals, including many Jewish students, and otherwise obstruct its once-venerable learning environment".

The Department of Homeland Security announcement said that "Noem demanded Harvard provide information about the criminality and misconduct of foreign students on its campus" and "Harvard University brazenly refused to provide the required information requested and ignored a follow-up request".

Speaking to China Daily minutes after the court ruling on Friday, Jiang, co-founder of Crimson Education, an education agency helping students navigate the admission process of US universities, said he was shocked when he found out the news was real.

"I saw this news at 2 pm in the afternoon. My first reaction was, this can't be true. I thought it was a rumor or fake news," he said.

Harvard has had a few "tug of war" encounters with the United States government in recent months, but Jiang thought the fight was over, as the government's withholding of funds from the Ivy League university had already been "quite impactful".

The Trump administration has frozen billions of federal funding to Harvard and opened an investigation into how it has handled antisemitism. In April, Harvard sued the administration over the funding.

"Then suddenly came this big news that we can't attend Harvard anymore," Jiang said. "All international students were given no time to prepare for this. It's quite shocking. Many of us felt angry, helpless and lost because US immigration law is very strict about legal status."

As Harvard didn't immediately issue any instructions to international students following the government's announcement, Jiang said many were panicking. However, he said he understands the university's position as it's such a big issue, and Harvard's leadership needs time to decide what to do.

University President Alan Garber issued a statement to the Harvard community on Friday morning condemning "this unlawful and unwarranted action".

"It imperils the futures of thousands of students and scholars across Harvard and serves as a warning to countless others at colleges and universities throughout the country who have come to America to pursue their education and fulfill their dreams," he said.

Garber refuted the DHS' claim the university had failed to comply with requests for information. "In fact, Harvard did respond to the department's requests as required by law," he said.

He also gave assurances to international students and scholars affected by the government's actions. "We will support you as we do our utmost to ensure that Harvard remains open to the world," he said.