The dispute started when one of the passengers used a gadget called the Knee Defender, which prevents the seat in front from reclining.

A law enforcement official says a woman asked a man to allow her seat to move but he refused.

He also refused a flight attendant's request to remove the device.

Officials say the woman threw a cup of water at the man.

The Newark, New Jersey, to Denver flight landed in Chicago and both passengers were removed.

Authorities say the passengers were not charged, but could face civil fines.