LOS ANGELES (AFP) - In yet another incident that could prove a public relations nightmare for the airline industry, a California couple has come forward claiming they were kicked off an overbooked Delta flight for refusing to give up their child's seat.

The incident unfolded last week as the Schear family of Huntington Beach were flying back home from Hawaii to Los Angeles.

In a video of the confrontation filmed and posted by the couple on YouTube, a flight attendant is overheard asking that they give up a seat occupied by their two-year-old son.

The father, Brian Schear, initially refuses on the grounds that the seat was paid for, but finally relents. He is nonetheless booted off the flight with his wife and two toddlers.

"This is a federal offence and then you and your wife will be in jail and your kids will be in foster care," the attendant is overheard telling Brian when he first refuses to disembark.

The video of the encounter, which was being widely shared on social media on Thursday (May 4), follows a number of similar incidents that have prompted outrage and proven a public relations fiasco for some of the airlines involved.

The most notable was that of a doctor who was left bloodied after being dragged off an overbooked United Airlines flight last month.

Delta airlines could not be immediately reached for comment on Thursday.

But in a statement to local media, the company said it was looking into the incident with the Schear family "to better understand what happened and come to a resolution."

Brian Schear said the family had to scramble to find a hotel room after being kicked off the aeroplane and paid US$2,000 (S$2,800) the next day for another flight, this time on United.

He said the seat he was asked to give up had originally been bought for his 18-year-old son Mason, who ended up going home on an earlier flight.

In the video, the Delta crew tries to coax him into giving up the seat, telling him that under federal regulations, two-year-old children must sit on a parent's lap during a flight.

Schear fired back that that argument did not hold up given that the toddler flew out in a separate seat on the way to Hawaii and was doing the same on the way back. The airline knew about it because they checked them in and assigned them seats, he said.

Delta's website seems to encourage parents to purchase a separate seat for children.

"We want you and your children to have the safest, most comfortable flight possible," the website states.

"For kids under the age of two, we recommend you purchase a seat on the aircraft and use an approved child safety seat."