Prosecutors investigating allegations surrounding a Seongnam land development project raided the office of lawyer Nam Wook, who owns an affiliate of the asset management firm at the center of the scandal.

The Seoul Central District Prosecutors' Office on Wednesday conducted a search and seizure at Nam's office in Seoul's Gangnam district.

Prosecutors reportedly obtained accounting files containing records that show the affiliate received a check for some 400 million won from Kim Man-bae, the biggest shareholder of the firm, Hwacheon Daeyu.

The investigation is focused on confirming whether Nam delivered the check to Yoo Dong-gyu, the former acting chief of Seongnam Development. Prosecutors suspect Yoo designed the profit distribution structure of the land development project so that Hwacheon Daeyu and its affiliates would reap outsize profits.

Another important figure in the scandal, accountant Jeong Young-hak, submitted to prosecutors a recording of a conversation containing information that Kim bribed Yoo with 500 million won made up of 400 million won in check and 100 million won in cash.