"You know, anybody would've done the same thing. It was just chaos," he told ABC News after returning home from his trip. "He was attacking passengers. We were trying to calm him down, he was whacked out."
A Korean Airlines representative told ABC News that there was an unruly passenger on Flight 480, and according to response protocol, Korean Air's flight attendants subdued him and tied him up with ropes.
The passenger was turned over to police after the plane arrived at Incheon Airport in South Korea, according to the airline.
One passenger sitting next to the man was injured, the airline representative said.
Marx, 53, offered a slightly different take on the events. The singer took to Facebook to share a series of posts about the incident, writing that the crew was "completely ill-equipped to handle the situation."
"We have video of entire chaotic and dangerous event," he wrote in one of his posts. "My wife and I are safe but one crew member and two passengers were injured. The all-female crew was clueless and not trained as to how to restrain this [man]."
An airline spokesperson explained that the passenger had drank two and a half shots of whiskey before turning violent. A flight attendant had considered using a Taser to subdue him, but decided against it out of fear for the safety of the other passengers, according to the spokesperson.
The spokesperson confirmed to ABC News that Marx had assisted in controlling the unruly passenger, but said that in the end a flight attendant tied the man up with rope.
The "Hold On to the Nights" singer was on the flight heading to Seoul with his wife Daisy Fuentes, he said.
"[The passenger] was only initially subdued when I and a couple other male passengers intervened. He then later easily broke his restraints and attacked more crew and another passenger. When we landed in Seoul police boarded the plane," Marx wrote in a post. "Heading home to Los Angeles soon but Korean Air should be sanctioned for not knowing how to handle a situation like this without passenger interference."
Marx posted various photos of the altercation on Facebook and Twitter, showing a man being restrained, as well as the singer helping out the flight attendants.
Korean Air said that it doesn’t respond directly to the opinions of individual passengers and that its flight attendants followed protocol and receive regular security training.
The Incheon International Airport police told ABC News that the passenger was sent home and could be called back for questioning pending an investigation.
A representative for South Korea's Ministry of Land, Infrastructure and Transport said that Korean law protects flight attendants' right to use Tasers but that fears over secondary damage to other passengers has limited their usage.
ABC News' Sang-Un Youn, Hye-Jin Choi, and Min-Soo Cho contributed to this report.