Jeong Jin-sang, center, a vice chief of staff to Democratic Party of Korea Chairman Lee Jae-myung, enters the Seoul Central District Court to attend his arrest warrant hearing, Nov. 18. Yonhap

A key aide to opposition leader Lee Jae-myung was indicted Friday on charges of receiving bribes amid speculation that the investigation will now head toward Lee.

The Seoul Central District Prosecutors Office charged Jeong Jin-sang, a vice chief of staff to Democratic Party of Korea Chairman Lee, as part of its widening investigation into a high-profile real estate development scandal allegedly connected to Lee.

Jeong is accused of taking about 240 million won ($184,000) from real estate developers between 2013 and 2020 in return for business favors for the project launched when Lee was the mayor of Seongnam, just south of Seoul, prosecutors said.

In return, Jeong ― who was put under pretrial detention ― was promised a 24.5 percent stake worth 42.8 billion won, they said.