Buffalo Bills head coach Sean McDermott says he “regretted" and “instantly apologized” for using a reference to the 9/11 terrorist attacks during a team meeting four years ago.

McDermott's 2019 comments about 9/11 resurfaced this week in a feature by independent NFL journalist Tyler Dunne, where he questioned the leadership style of the seven-year head coach as the Bills sit at 6-6 on the season. According to multiple sources cited in Dunne's feature on GoingLongTD.com, McDermott told his team that they need to come together like "the terrorists on Sept. 11, 2001."

"He cited the hijackers as a group of people who were able to get on the same page to orchestrate attacks to perfection," Dunne reported.

McDermott confirmed the report on Thursday in a news conference, where he explained that he fell short of highlighting the significance of communication. "My intent in the meeting that day was to discuss the importance of communication and being on the same page with the team. I regretted mentioning 9/11 in my message that day and I immediately apologized to the team," he said in a press conference.

What did Sean McDermott say about 9/11?

According to Dunne, McDermott's training camp speech in 2019 is infamously known amongst the team as his “9/11 speech." During the speech in Pittsford, New York, McDermott "started asking specific players in the rooms questions. 'What tactics do you think they used to come together?'"

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When asked what the terrorists' biggest obstacle was, Dunne reported that a veteran answered "TSA," a response that "lightened the mood."

Sean McDermott apologized to team after 9/11 speech

In a press conference held Thursday in light of Dunne's feature, McDermott said he apologized to his team in 2019, the same day he gave the 9/11 speech after an unnamed player questioned his message.

“One player didn’t seem – that I didn’t make my point clear enough,” McDermott said Thursday, according to The Buffalo News. “So right then and there I said we’re getting together as a team and I’m going to address this with everyone. That was before practice. So we had a team meeting and within an hour – this is a few years ago – so within an hour, and it was actually at the start of practice, I brought everybody together and said this was the goal, this was the intent, and I apologize if anyone whatsoever felt a certain type of way coming out of that meeting."

He continued: “If anyone misinterpreted or didn’t understand my message, I apologize. I didn’t do a good enough job of communicating clearly the intent of my message. That was about the importance of communication and that everyone needs to be on the same page, ironically enough. So that was important to me then and still is now.”

What's next?

McDermott, who said he hadn't read Dunne's feature in full, said he plans to meet with his team Thursday in light on the resurfaced comments. "Not only was 9/11 a horrific event in our country's history, but a day that I lost a good family friend," McDermott added.

The controversy surrounds McDermott and the Bills as they get ready to take on the Kansas City Chiefs (8-4) at Arrowhead Stadium in Kansas City on Sunday as they fight to keep their playoff hopes alive. Buffalo, which has lost three of its last five games, is coming off a bye week following a 37-34 overtime loss to the Philadelphia Eagles.

McDermott was already on the hot seat following his team's surprising 6-6 start to the season and his resurfaced comments may add fuel to the fire.