United CEO Oscar Munoz has shared the airline's official recap of an incident in which law-enforcement officials on Sunday forcibly removed a passenger from one of the company's flights.

The sequence of events is based on preliminary reports submitted by the airline's employees:

"Summary of Flight 3411

• On Sunday, April 9, after United Express Flight 3411 was fully boarded, United's gate agents were approached by crew members that were told they needed to board the flight.

• We sought volunteers and then followed our involuntary denial of boarding process (including offering up to $1,000 in compensation) and when we approached one of these passengers to explain apologetically that he was being denied boarding, he raised his voice and refused to comply with crew member instructions.

• He was approached a few more times after that in order to gain his compliance to come off the aircraft, and each time he refused and became more and more disruptive and belligerent.

• Our agents were left with no choice but to call Chicago Aviation Security Officers to assist in removing the customer from the flight. He repeatedly declined to leave.

• Chicago Aviation Security Officers were unable to gain his cooperation and physically removed him from the flight as he continued to resist — running back onto the aircraft in defiance of both our crew and security officials."

This account of Flight 3411 is purely from the perspective of the airline. While we do not yet have a first-hand account from the unidentified passenger at the center of the incident, witnesses aboard the flight have criticized law-enforcement and United for what they viewed as unnecessarily brutal tactics.

The US Department of Transportation is reviewing the events that occurred on the flight with a focus on potential rules violations.

In addition, one of the officers involved in the removal of the passenger has been placed on leave.

Munoz commends employees for going 'above and beyond'

Munoz wrote an open letter to the airline's 82,000 employees following the ordeal. In the letter, Munoz reaffirmed his support for United's employees while saying there were lessons to be gleaned from the incident.

The CEO, however, stopped short of apologizing to the 69-year-old customer.

Reaction to the disturbing footage of the incident has been immediate and visceral, with United taking the brunt of the public's anger. The situation was not helped by a poorly executed statement from Munoz earlier Monday that seemed to add fuel to the fire.

Here's the letter to employees from Munoz:

"Dear Team, Like you, I was upset to see and hear about what happened last night aboard United Express Flight 3411 headed from Chicago to Louisville. While the facts and circumstances are still evolving, especially with respect to why this customer defied Chicago Aviation Security Officers the way he did, to give you a clearer picture of what transpired, I've included below a recap from the preliminary reports filed by our employees.

"As you will read, this situation was unfortunately compounded when one of the passengers we politely asked to deplane refused and it became necessary to contact Chicago Aviation Security Officers to help. Our employees followed established procedures for dealing with situations like this.

"While I deeply regret this situation arose, I also emphatically stand behind all of you, and I want to commend you for continuing to go above and beyond to ensure we fly right. I do, however, believe there are lessons we can learn from this experience, and we are taking a close look at the circumstances surrounding this incident.

"Treating our customers and each other with respect and dignity is at the core of who we are, and we must always remember this no matter how challenging the situation.

"Oscar"