An underage apprentice sumo wrestler has been the subject of repeated physical abuse and bullying at the stable run by Bulgarian-born former ozeki Kotooshu, the Japan Sumo Association announced Thursday.

According to the JSA, a 20-year-old, fourth-tier sandanme wrestler subjected an apprentice at the Naruto stable to a judo-style choking move as punishment for failing in his duties.

The JSA has been dealing with a string of physical abuse scandals for more than a year, since former yokozuna Harumafuji retired at the end of 2017 after assaulting a lower-ranked wrestler.