A prominent French historian has said he was detained for more than 10 hours in Houston and threatened with deportation, in the latest of several examples of high-profile individuals being questioned extensively at US airports before being allowed entry.

Henry Rousso flew from Paris to Houston last Wednesday to take part in a symposium at Texas A&M University but was wrongly detained and almost sent back to France after a border guard failed to understand Rousso’s entitlements under visa rules, university officials said.

Rousso said on Twitter that he was “detained 10 hours at [Houston’s George Bush intercontinental airport] about to be deported. The officer who arrested me was ‘inexperienced’.”

While he was held, Rousso contacted university officials who attempted to secure his release. “He was waiting for customs officials to send him back to Paris as an illegal alien on the first flight out,” Richard Golsan, a professor at Texas A&M, told the Eagle.

Following scorn poured on Donald Trump by the French president and the mayor of Paris after the US president suggested in a speech last week that Paris is unsafe for American tourists, the incident has sparked fresh outrage in France. Emmanuel Macron, a presidential candidate, tweeted on Sunday to declare that “there is no excuse for what happened to Henry Rousso. Our country is open to scientists and intellectuals.”

Fatma Marouf, director of the A&M Immigrant Rights Clinic, told the Guardian on Sunday that she found out about Rousso’s situation at about 10pm on Wednesday night and worked to get him freed, which happened three or four hours later. She said that Rousso came to the US on a visitor’s visa which normally does not allow recipients to work or receive compensation, but there are exceptions for some academic activities, such as giving lectures or speeches.

“My best guess is that it was his honorarium, I don’t think the officer who decided to detain him really understood the visa requirement and the technicalities on getting an honorarium which are permitted under his visa,” Marouf said. A Customs and Border Protection spokesperson did not immediately respond to a request for comment.

Raised in France after his family were exiled from Egypt, the country of his birth, the 62-year-old Rousso is an expert on antisemitism and the Vichy government in France during the second world war and writes and lectures on the importance of remembering and learning from that period in modern history. He works at the French National Centre for Scientific Research. He has also had links with several distinguished American institutions, including Columbia University, Harvard University, Yale University and the US Holocaust Memorial Museum.

After landing in Houston he was taken to an interview room where an officer suspected him of travelling on another, expired, visa, he wrote in the Huffington Post’s French edition.

He credited the intervention of the university officials with securing his release and said he did not know why he was singled out for special scrutiny, but doubted it was by chance. “I’m always wary of making any hasty conclusions. This incident has caused me a certain discomfort, it’s impossible to deny. I cannot, however stop myself from thinking of all those who have to suffer these humiliations and this legal attack without the protections which I was able to benefit from,” he wrote.

“It is now necessary to face up to the total arbitrariness and incompetence on the other side of the Atlantic,” he wrote. “I don’t know which is worse. What I do know, loving this country as I always have, is that the United States is no longer quite the United States.”

Last week it was reported that border agents in Florida detained the US citizen son of the boxer Muhammad Ali and asked if he was a Muslim, while the celebrated Australian children’s author Mem Fox said she “collapsed and sobbed like a baby” after being held at Los Angeles international airport for two hours, insulted and questioned about her visa status.

Rousso did not immediately return a comment request on Sunday. He is scheduled to fly back to France on Sunday – accompanied to the airport by a French consulate official to ensure his check-in process goes smoothly, Golsan told the Guardian.

Two more French academics are set to visit Texas A&M for a conference this week, he said. Golsan added that there was concern in the academic community that Rousso’s predicament was a sign that the anti-immigrant “spirit of Trump” has emboldened enforcement officials to behave overzealously. The professor said that even though an immigration agent called him to confirm details in Rousso’s story at about 4.30pm on Wednesday, he was not released for another eight hours or so and grew anxious that he might be shackled and handcuffed if forced to fly back to France.