Down syndrome teen banned from American Airlines flight (VIDEO)

A California family claims American Airlines banned them from boarding a recent cross-country flight because their son has Down syndrome.

Joan and Robert Vanderhorst were flying on American Airlines from Newark, New Jersey, to Los Angeles on Sunday with their 16-year-old son Bede, Los Angeles TV station KTLA reported.

As they waited to board the flight, the couple said they were told they wouldn't be allowed on the plane.

Joan Vanderhorst took out her cellphone and began recording the incident, in which an American Airlines employee labeled Bede as a "flight risk."

In the video, Bede Vanderhorst is seen sitting at the gate, quietly playing with his hat.

His mother can be heard sobbing and his father expressing disbelief.

"He's behaving," Robert Vanderhorst says. "He's demonstrating he's not a problem."

American Airlines is standing behind its decision to remove the boy from the flight, telling the New York Daily News that he was "agitated" in the waiting area.

"Asking the family to take the next flight was a decision that was made with careful consideration and that was done based on the behavior of the teen," the airline said.

Joan and Robert Vanderhorst told Bakersfield, Calif., TV station KERO they plan on suing the airline for defamation and violating their son's civil rights.