James Long, a former Chicago aviation security officer, who was fired after forcibly removing a passenger off a United Airlines flight last year, has filed a lawsuit against the airline and the city. The lawsuit was filed against United, Long's former employers at the Chicago Department of Aviation, and the department’s commissioner, Ginger Evans.

Long alleged in his lawsuit, which was filed in Cook County Circuit Court on Tuesday, he was not trained on how to use force, and that United Airlines should have known that removing David Dao from the flight would require “physical force.”

“But for the CDA’s negligence and failure to train [Long] how to respond to an escalating situation with an Airline Passenger, [he] would not have acted in the manner he did, which resulted in his termination,” the lawsuit states, according to the Chicago Tribune.

Long accused Evans of defaming him while speaking with the press following the incident and also tweeting that the officers' actions were “completely inappropriate” and that they aren’t armed “for good reason.”

Evans made “deliberate and intentionally misleading omissions with the direct intention to harm” Long, the lawsuit claimed.

Long is suing the airline, the city and the commissioner seeking over $150,000 in damages, including back pay stemming from his termination in August.

The United Airlines controversy took place in April last year when Dao, a 69-year-old Vietnamese-American physician, was dragged out of the plane after refusing to give up his seat to airline employees. The flight was scheduled to travel from Chicago to Louisville, Kentucky. Due to the use of excessive force to remove him from the jet, Dao suffered a concussion, a broken nose and two knocked-out teeth. He also reportedly required surgery for a sinus problem.

The handling of the incident received widespread condemnation after video of the incident went viral on social media, leading to the firing of Long, and Dao receiving "millions" in settlement. 

Following the incident, United Airlines CEO Oscar Munoz said the company was reviewing its policies to ensure no other passengers would be subjected to such situations.

“Dr. Dao has become the unintended champion for the adoption of changes which will certainly help improve the lives of literally millions of travelers,” one of Dao’s lawyers, Thomas Demetrio, said at the time. “I sincerely hope that all other airlines make similar changes and follow United’s lead in helping to improve the passenger flying experience with an emphasis on empathy, patience, respect and dignity.”

united-airlines_0 A former Chicago aviation security officer who was fired after forcibly removing a passenger off a United Airlines flight in 2017, has filed a lawsuit against the airline. In the picture, United Airlines planes sit on the tarmac at San Francisco International Airport, July 8, 2015. Photo: Getty Images/Justin Sullivan