Over two dozen people are being investigated in a drug scandal surrounding former professional baseball player Oh Jae-won, Seoul police said Wednesday.

Seoul Gangnam Police Station said it has forwarded the case to the prosecution, with 29 people facing charges of violating the Narcotics Control Act.

The list includes 13 active or retired pro baseball players, a trainer for Oh's former team the Doosan Bears of the KBO, parents of a player from Oh's baseball academy, three people who provided illegal drugs, two hospital officials and a woman believed to have used methamphetamine with Oh. All nine of the active players are currently playing for the Bears.

Oh, 39, is suspected of habitually using methamphetamine and psychotropic medications, and of threatening an acquaintance who attempted to report his drug use. He is also accused of illegally obtaining sleeping pills by having acquaintances obtain prescriptions.

An internal inquiry by the Doosan Bears found that eight players were involved in illegally providing the sleeping pills to Oh. The Seoul Metropolitan Police Agency in May revealed that five more active and retired players are suspected to be involved.

Oh has already been indicted and is being tried. But police have been conducting an extended investigation on those allegedly linked to his drug use.

Officials believe that Oh used the illegal substances from early 2020, before he retired from baseball in October 2022.

Oh, an infielder who played the entire 16 seasons of his pro career with the Seoul-based Doosan Bears, was a key role player in the team’s three KBO championships in 2015, 2016 and 2019. He was also a fan favorite who had a reputation of being one of the kindest players with the team's supporters.