In August, I reported on two, separate aviation-security incidents that took place on Frontier Airlines flights in a 36-hour period. Now there has been a third incident. Passenger Timothy Furnas, a business executive from the west coast, described what happened on Frontier Airlines Flight 623 — flying from Denver to Detroit last Sunday — in this exclusive interview: 

"I was in seat 21-A, next to the last row of the plane. It was a full flight, fairly uneventful. Looking back at the flight, after what happened at the end, the only thing that hinted to the fact that something was going on was a flight attendant's announcement mid–flight. She came on the intercom and said in a very stern voice, not quite but almost a panic: 'You must go back to your seats. You can not congregate near the bathroom at the front. There are two bathrooms in the back.'

I've heard that announcement — or something like it — many times before. What was unusual was how stern and serious she sounded when she said it.

When we landed in Detroit, a flight attendant made another stern announcement. She said we must remain in our seats, with our seatbelts fastened, even after we arrived at the gate. She repeated this, sounding very serious.

The door opened and seven police officers rushed onto the plane. Right around row six or seven, they went into the overhead bin. They grabbed a bag. Then they grabbed the man in the seat below and they rushed him off the plane. Everyone was silent. I think it took us all by surprise. Then the flight attendant came on the intercom, apologized and said we could all go ahead and get off the plane.   

In the gate area, the man had been taken off to a corner. There were about eighteen police officers surrounding him and two guys in suits. The suits got my attention. They were asking the man questions. He was semi-yelling at them. He looked either Arab or Cuban. The man was late forties, early fifties and he had a very scruffy beard, like Castro did when he was younger.

Yesterday [Tuesday, October 9], when I went to the Frontier [Airlines] counter to check in for my flight back home, I asked the guy at the counter if he'd heard anything about what happened on Sunday.

He said, 'I was here on Sunday.' 

Again, I asked him what happened.

'I can't tell you,' the [Frontier gate agent] said. 'I can apologize, but I can't tell you.'

I said I understood.

'I can tell you this much,' he said. 'An Arab man locked himself in the front bathroom for the majority of the flight. And at orders, he refused to come out. That wasn't the end of the story, but I can't tell you any more.'

I thanked the guy for telling me that. When I look back, what struck me during the flight on Sunday, knowing this new information, was that the flight attendants didn't give us any signs that anything was really wrong during the flight. They were very professional. When something like this happens, it makes me what to know more. It makes me wonder how often this kind of thing goes on, and why it's not reported."

Mr. Furnas provided The Aviation Nation with copies of his airline tickets for this story.