The unnamed athlete also said the coach had taken money from him to pay for training sessions, the Yonhap News Agency said, adding that prosecutors in Incheon were investigating the reports.

"During the Paralympics, the coach one night returned home drunk and hammered the athlete's head with a light stand," a friend of the athlete told Yonhap.

"He has been abusing him frequently since 2010.

"The athlete is ranked number one in the world but couldn't win a medal because of injuries he sustained from the coach's abuse." 

South Korea finished ninth in the overall medals table at London 2012 with a total of 27 medals, nine of which were gold.

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