The remorse of the ticket inspector who allowed terrorists onto the plane on September 11th.

On September 11, 2001, two men arrived late at the check-in counter to board American Airlines Flight 77 departing from Washington. Checker Vaughn Allex examined their documents and let them through.

Mr. Vaughn Allex and his wife, Denise. Photo: StoryCorps

However, those two passengers were among the five hijackers who seized the plane and crashed it into the Pentagon, killing 189 people, including the terrorists, according to NPR.

"I didn't know what I had done," Allex recalled. He didn't know what had happened until the next day either. "I went to work and found that everyone was avoiding eye contact."

Government officials gave Allex a flight declaration form. "I glanced at it for a moment, then looked up and walked away. 'Did I do that? Was that really me?'" he shared.

Allex handled check-in for a retired family on the flight, a group of students, their parents, and even their teacher. "They're all gone," he said.

Allex said people stopped talking to him as things became clearer. He started to think that he was the cause of what happened, and perhaps he could have changed something if he had acted differently.

Allex understood that many people around him were struggling to cope with the grief of losing a loved one, but he felt uncomfortable joining support groups.

"How can I sit in the same room with people who are crying and grieving? They might think about my role in the incident," Allex explained. "What should I tell them? 'I processed the paperwork for the two hijackers and let them board the plane.'"

Weeks, even months, passed, and Allex continued to harbor this guilt. Just mentioning 9/11 would trigger a surge of remorse in him. A client once told Allex that her husband was a victim of the 9/11 attacks, but he misheard her as, "You killed my husband on 9/11."

Allex says that to this day he still hasn't been able to put the past aside. In one way or another, it still haunts him. But over time, Allex is gradually becoming able to talk about it.

"I feel like I've truly stepped out of the darkness for the past 15 years," Allex said. "Now I'm back in the light."

According to VNE