Southern California News Group (SCNG) also reported the under-fire national governing body had been aware of the allegations since at least the summer of 2017.

According to SCNG, the complaints of emotional and verbal abuse were made against New Heights Gymnastics club and owner Amy Nyman.

SCNG reported the accusations were serious enough to be passed on to the U.S. Center for SafeSport in February.

In an interview with the organisation, Nyman denied wrongdoing but admitted he had discussed the complaints with a USA Gymnastics lawyer before being appointed to his position.

This was denied by USA Gymnastics, who accused him of making "false statements" and breaching confidentiality.

USA Gymnastics' announcement that it had terminated Nyman's contract sparked further controversy and called into question the stewardship of the recently-installed chief executive Li Li Leung, the fourth official to hold the role in 23 months.

It also raises concerns as to the vetting process carried out by USA Gymnastics when selecting candidates for high-profile roles.

The sacking of Nyman marked the third time since August that a USA Gymnastics management appointment had lasted less than a week – Mary Bono was interim chief executive for just four days and Mary Lee Tracy was asked to resign three days after being named elite development coordinator.

The organisation said Nyman's departure had occurred due to a conflict of interest.

At the time, the body did not provide further comment but USA Gymnastics has now confirmed the reason behind the decision.

"Dr. Nyman was terminated for his failure to disclose athlete safety complaints involving the club with which he is affiliated to USA Gymnastics,” USA Gymnastics said in a statement issued to SCNG. 

"This demonstrated poor judgment and created a conflict of interest that disqualified him from serving in this important role. 

"We are confident this was the best decision for the welfare of our athletes and our community."

USA Gymnastics' status as the national governing body for the sport remains in doubt after the United States Olympic Committee (USOC) began a process to decertify the organisation following the Larry Nassar sexual abuse scandal.

In March, the USOC decided against moving forward with the process to revoke the membership of USA Gymnastics while it remains in bankruptcy proceedings.

The decision has been criticised by U.S. Senate finance committee chairman Charles E. Grassley, who has given USOC a May 10 deadline to provide an explanation.