Vilma Soltesz TV2.hu A 425-pound woman died last month in Hungary after three airlines allegedly told her she was too fat to fly back to America.

Janos Soltesz plans to sue Delta, KLM, and Lufthansa next month, claiming the airlines are responsible for his wife Vilma Soltesz's death after all three refused to fly her back to America — even though Delta and KLM flew her to Hungary without complaint, the New York Post reported Tuesday.

The Solteszs spent three weeks in their native Hungary before Vilma needed to come back for treatment for diabetes and renal disease.

“Very rarely do you have discrimination causing much more than humiliation and psychological damages, but in this instance, the discriminatory actions of the airlines led to something much more serious — Vilma’s death,” Soltesz's lawyer Holly Ronai told the Post.

Soltesz is seeking a total of $6 million from the three airlines.

The U.S. Department of Transportation is investigating Vilma's death, according to the Post.

But Lufthansa is telling a much different story.

"Of course nobody said she was too fat to fly home," spokesman Nils Haupt told Business Insider.

The airline says it actually reserved three seats for Vilma, who had to be brought onboard the plane by a special lift. But once she was on the aircraft, Haupt says, it was impossible to move her from her wheelchair to her plane seats.

"There was not the slightest idea how to move her out of the wheelchair without hurting her," Haupt said.

Crews tried to move Vilma for about 30 minutes before she was taken off the plane, according to Haupt.

In a statement sent to Business Insider, KLM said it was "deeply saddended" by Vilma's death but that when she tried to fly home it appeared "it was not physically possible for her to board the aircraft, despite every effort made by KLM to this end. A seat or belt extender did not offer a solution either."

In a statement emailed to Business Insider, Delta spokesman Russell Cason said the airline was "physically unable to board" Vilma on a flight.

However, both Delta and KLM "did everything possible to assist the family."

This isn't the first time airlines have come under fire for allegedly refusing passage to customers they deem overweight.

Filmmaker Kevin Smith lambasted Southwest Airlines in 2010, claiming a pilot ejected him from a flight because he was too fat to fly, ABC News reported at the time.

Smith went on Twitter tirade against the airline, Mashable reported at the time:

Dear @SouthwestAir – I know I’m fat, but was Captain Leysath really justified in throwing me off a flight for which I was already seated?

Wanna tell me I’m too wide for the sky? Totally cool. But fair warning, folks: IF YOU LOOK LIKE ME, YOU MAY BE EJECTED FROM @SOUTHWESTAIR.

Dear @SouthwestAir, I’m on another one of your planes, safely seated & buckled-in again, waiting to be dragged off in front of the normies.

Southwest ultimately tweeted an apology to Smith.

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