A flight from Philadelphia to Syracuse, New York, was delayed for two hours on Thursday after a woman expressed fears to the cabin crew that the man sitting next to her was a terrorist scribbling some sort of terrorist code into a notepad. In reality, he was a 40-year-old tenured professor at the University of Pennsylvania who was working on a differential equation.

American Airlines, whose regional partner Air Wisconsin operated the flight, confirmed the woman had raised suspicions about Guido Menzio, who has “dark, curly hair, olive skin and an exotic foreign accent,” according to the Washington Post. Menzio is Italian.

It seems the woman at first said she was feeling sick, but then when she stepped off the the airplane told the crew she didn’t feel comfortable flying because of the man sitting next to her. Security personnel intervened and quickly determined the economics professor wasn’t a threat to anyone. The woman who had raised concerns never reboarded the flight.

Menzio insists he was “treated respectfully throughout” but says the whole incident served to illustrate a “broken system that does not collect information efficiently” and that anyone can end up causing a flight to be delayed for hours, no matter how ridiculous the suspicion.

This incident took place a month after a Berkeley student was kicked off a Southwest flight when a fellow passenger reported him when she overheard him speaking Arabic.