"The man did nothing more than sit in the wrong seat," the passenger's lawyer, Howard Schaffner, told ABC News.
David Ukesone, a 71-year-old retired police officer in Nigeria, was on the second leg of his journey to the US on January 23 when the altercation took place.
He had recently been granted a US visa and was planning on joining his wife, who had moved to the US four months ago, and his children.
According to Schaffner, it was the first time in 35 years that Ukesone had flown on a plane.
His first leg of the trip — from Nigeria to Dubai — went smoothly. However, eight hours before landing in Chicago, his trip quickly went haywire.
— Aruogu Amanda (@armadanews1) January 30, 2018
He reportedly got up from his assigned seat — 35D — to use the bathroom. He sat down in the wrong seat by mistake after returning from the restroom.
Ukesone was sitting in a seat in the reserved section that was "very close" to his assigned seat, Schaffner explained.
"He was asked to move and he wants to take his bag in the overhead compartment with him," the attorney told ABC news.
Ukesone, who speaks English, has difficulty understanding the language when it is spoken by a non-Nigerian.
Precise details about what followed are sparse.
"He didn't think he was in the wrong seat and there was an argument… they laid hands on him to move him and that's when everything escalated," he explained, also adding that Ukesone suffered "significant wounds on his wrists and ankles" from the airplane staff.
Ukesone's mouth was also taped shut for the rest of the flight and he wasn't offered any food or water.
After the plane landed at Chicago O'Hare International Airport, he was wheeled off the plane in a stretcher and taken to the University of Chicago Medical Center while his son, who was waiting at the airport, had no idea where his father was.
"He's [Ukesone's son] is waiting for hours and he starts to check and ask people about his dad," the lawyer said.
Ukesone spent four days in the hospital as a result of his experience.
"There's no question we're going to file a lawsuit," Schaffner told ABC news.
"Everybody needs to step back for a second and take a deep breath," Schaffner said. "He hasn't flown in a long time and he's clearly from another country… he just made an honest mistake of sitting in the wrong seat and people have to be trained to deal with things like that, without escalating them into something crazy."
There were no arrests or police reports documenting the incident.
Emirates confirmed to ABC News that a passenger was removed from a flight last week.
"The safety of our passengers and crew is of the utmost importance and will not be compromised," the airline said in a recent statement.
