Knee Defender airplane - a device that is supposed to provide plane passengers relief during a flight has led to discomfort that sent two travelers fighting over personal space.

According to USA Today, a bizarre incident happened on Sunday when the United Airlines Flight 1462 bound for Denver from Newark, New Jersey was diverted to Chicago's O'Hare International airport over a brawl between two passengers that all started with the Knee Defender airplane contraption.

The Associated Press reports that the Knee Defender airplane contraption - a device that prevents airline seats from reclining - led two of the United Airlines Flight 1462 passengers to fight one another over personal space.

One man, who was seated in the Economy Plus section of the plane, was said to have used a $21.95 gadget called a Knee Defender to prevent the woman seating in front of him from reclining her seat.

Though the intention of the man was of course to defend his knees from possible irritation, discomfort and pain from a reclining chair, it appears that the woman seating in front of him was not at all pleased with his Knee Defender airplane contraption.

The woman reportedly alerted a flight attendant to ask the man if he could just remove the Knee Defender airplane device at the back of her seat so she could recline it.

When the flight attendant sincerely approached the man and asked him if he could grant the woman's request, he refused to remove the device in front of his legs.

It isn't clear how he voiced out his disagreement, but reports say the woman got so mad that she stood up and threw a cup of water at the male passenger.

The succeeding details were not divulged by a law enforcement official, but it is believed that things got really serious such that the pilot decided to divert the flight to Chicago.

United Airlines spokesman Charles Hobart explained via email that unlike the Federal Aviation Administration that does not actually prohibit the use of the Knee Defender airplane device "we do not allow customers to use devices that prevent seats from reclining.

It is not clear whether the Knee Defender user passenger was informed of United Airlines' rule on using the said contraption.

Nevertheless, because of the serious fight the two passengers caused during the flight, they were asked to depart from the plane so that the rest of the travelers can fly towards their destination.

"Authorities met the aircraft, removed the two passengers and the flight continued to Denver shortly afterwards," Hobart said.

According to the Transportation Security Administration spokesman Ross Feinstein, the passengers that caused the flight to divert were not arrested because the incident "was deemed a customer service issue and not a threat to aviation security."

On the other hand, Knee Defender inventor Ira Goldman expressed his thoughts on the incident after hearing about it through mainstream media.

"Sometimes people do things they shouldn't do on airplanes, but as far as I know this is the first time anything like this has happened," Goldman said.

"United could make seats that do not recline, but they have not chosen to do so," he added. In the meantime, the Knee Defender says right on it: 'Be courteous. Do not hog space. Listen to the flight crew.' Apparently that is not what happened here."

Interestingly, after the incident was reported nationwide, the Knee Defender website crashed because of the large number of people who attempted to access it, reported International Business Times.

The site maintains: "If the airlines will not protect people from being battered, crunched, and immobilized -- very real problems according to healthcare professionals, medical studies, government agencies, and even some airlines -- then people need options to protect themselves."

The passengers involved in the Knee Defender airplane fight have not been named by authorities.