The number of gymnasts involved in a legal action against British Gymnastics over alleged "systemic physical and psychological abuse" has more than doubled in the last month to 37 and represents the "tip of the iceberg", according to their representatives.
A letter on behalf of 17 gymnasts, some of whom were as young as six, alleging abuse by coaches was served on the sport's governing body in the UK by law firm Hausfeld in February.
That number has now increased substantially, with Hausfeld threatening to take the matter through the courts if British Gymnastics does not provide a substantive response by June 19.
Hausfeld had wanted a response to their February letter by this Thursday.
British Gymnastics had, according to Hausfeld, asked for an extension until December 19, something those involved in the action feared would put "current gymnasts at risk of similar serious harms".
"We're disappointed but not surprised that British Gymnastics have failed to meet the reasonable deadline we set," a spokesperson for the group legal action said.
"Every day that they delay, former gymnasts are denied the justice they so richly deserve -- and current gymnasts are at risk of similar serious harms.
"Since we issued our letter before action a further 20 gymnasts have come forward, representing the tip of the iceberg in terms of the number of gymnasts who allege they have been harmed over a 40-year period.
"We now look forward to hearing from British Gymnastics by no later than June 19, 2021."
The spokesperson added: "If British Gymnastics do not put their full organisational weight behind addressing our case, then we will take the opportunity for British Gymnastics to be part of reforming the sport we love out of their hands and into the courts."
An independent review to look into complaints of mistreatment within the sport is currently under way.
Jennifer Pinches, who retired from international competition after helping Team GB reach the final at the 2012 London Olympics, said last month that British Gymnastics had spent too long prioritising "podiums over people".
"It is a heart-breaking truth to face, knowing the level of abuse that we and so many others were subjected to," added Pinches, who is now the community director of the Gymnasts for Change group.
The group wants British Gymnastics to make a formal apology, provide compensation and improve coaching guidelines.