A citizens’ group has filed a criminal complaint against Tokyo Gov. Naoki Inose for receiving ¥50 million from a hospital chain at the center of his campaign money scandal, sources said Monday.

The group headed by Tamaki Mitsui, a former public prosecutor, sent the complaint against Inose — as well as Torao Tokuda, former chief of the Tokushukai hospital group, and Takeshi Tokuda, his son and a member of the Lower House — to the Tokyo District Public Prosecutor’s Office, the sources said.

The group claims the Tokudas conspired to hand ¥50 million to Inose prior to the December 2012 gubernatorial election that he won, in a Diet office building around Nov. 19 last year, but that Inose failed to record the money in his mandatory campaign report.

Inose has said the money was a personal loan, not a campaign contribution, and he wrote a document acknowledging such.

He also said he returned the money to the elder Tokuda’s wife through one of his secretaries in September after prosecutors launched an investigation into the Tokushukai group on Sept. 17 on suspicion of illegally rewarding people who worked on the younger Tokuda’s election campaign in December 2012.

However, Tokuda’s wife has said she is unaware the loan was a personal one. According to records held by the Tokushukai group, Inose sought ¥100 million from the group for his political campaign.