A college student who came to the United States as an Iraqi refugee was removed from a Southwest Airlines flight in California earlier this month after another passenger became alarmed when she heard him speaking Arabic.

The student, Khairuldeen Makhzoomi, a senior at the University of California, Berkeley, was taken off a flight from Los Angeles International Airport to Oakland on April 6 after he called an uncle in Baghdad to tell him about an event he attended that included a speech by United Nations Secretary General Ban Ki-moon.

“I was very excited about the event so I called my uncle to tell him about it,” he said.

He told his uncle about the chicken dinner they were served and the moment when he got to stand up and ask the secretary general a question about the Islamic State, he said. But the conversation seemed troubling to a nearby passenger, who told the crew she overheard him making “potentially threatening comments,” the airline said in a statement.

Mr. Makhzoomi, 26, knew something was wrong as soon as he finished his phone call and saw that a woman sitting in front of him had turned around in her seat to stare at him, he said. She headed for the airplane door soon after he told his uncle that he would call again when he landed, and qualified it with a common phrase in Arabic, “inshallah,” meaning “god willing.”