One of Britain's greatest Paralympians has claimed fellow athletes have been threatened with deselection if they speak out about abuse of the classification system.
Baroness Tanni Grey-Thompson, who won 11 gold medals in her Paralympics career, told MPs the current system of determining an athletes category is neither fair nor transparent.
Those who wanted to speak out against abuse of the system - by those who may be misrepresenting a disability to get an edge in a specific category - have allegedly faced bullying and threats.
It was announced last week the classification rules would be revised.
"The repercussions that were reported to me were things like deselection from the squad or the team, lack of access to funding, lack of media coverage," Baroness Grey-Thompson told MPs at a select committee hearing.
One medal winner has even handed back a medal she won, over concerns about the system.
Bethany Woodward has turned her back on the sport, and she thinks her team won a relay unfairly due to classification.
She told ITV News: "They're wanting these medals so much that they are completely forgetting what the Paralympics is about. I don't believe that athletes on the grass roots are to blame. This is to do with an organisation which is ripping Paralympic sport apart."
One father of a swimmer said "there’s certainly corruption" in British Australian, Canadian and American swimming.
Mark Hanson said he has seen those competing against his daughter Levana misrepresenting their disabilities, and added parents know about it but don't want to speak up because their children's sporting career could suffer as a result.
- Levana and Mark Hanson
The British Paralympic Association's boss defended the system, telling MPs he's seen no evidence of deliberate classification cheating.
Tim Hollingsworth said: "Where we have interaction with athletes, with coaches, with sports, these issues were not made clear in the way they are being today, at that time and to us."
The International Paralympics Committee said in a statement that a classification review is planned, but it also raised concerns about "repeated and unfounded allegations".