Kohei Nakabo, adviser to Resolution and Collection Corp., has resigned and a senior managing director and four others of the debt-collection vehicle have been punished over an improper collection deal in 1998, RCC chief Akio Kioi said Friday.

The resignation of Nakabo, a former RCC chief, and the punishments are both effective Thursday, Kioi said.

RCC Senior Managing Director Kaoru Nakajima has been demoted to a managing director, Kioi said at a news conference.

The RCC has also canceled its contract with lawyer Takao Takeuchi, who was in charge of the deal in question, Kioi said.

By the end of last year, Nakabo, Nakajima and Takeuchi had already expressed their intentions to resign.

Kioi said, "I apologize for a treasonous act that undermines related creditors' trust in actions being carried out by us." The deal in question, which took place in 1998, involved a loan to an abortive hotel construction project for the purchase of a plot of land in Sakai, Osaka, according to RCC officials.

While the RCC collected its portion of claims by selling the part of the land on which it held the mortgage, it failed to provide relevant information -- such as the assessed value of the whole lot -- to financial institutions that had claims on other parts of the land.

At that time, Nakabo headed the RCC and Nakajima was a managing director in charge of the deal.