Prosecutors on Friday questioned a former finance minister and head of the state-run Korea Development Bank (KDB) on charges of bribery, about two months after a court refused to issue a warrant to arrest him.

Kang Man-soo, 71, appeared at the Seoul Central District Prosecutors' Office in the morning to undergo interrogation by the prosecution team looking into a massive corruption scheme surrounding Daewoo Shipbuilding & Marine Engineering Co., according to prosecutors.

Kang was the country's finance minister from 2008 to 2009 under the Lee Myung-bak administration and then served as the KDB chief from 2011 to 2013.

He is accused of receiving hundreds of millions of won in kickbacks from Hansung Enterprise Co., a local seafood maker, since 2008.

Prosecutors also suspect that he pressured Daewoo Shipbuilding into investing in a local biotech firm run by his friend in return for overlooking irregularities committed by then head of the shipyard Nam Sang-tae.

The KDB is the largest shareholder of the financially troubled shipbuilder.

Daewoo Shipbuilding decided to provide 5.5 billion won ($4.65 million) for the biotech firm's research project in 2012 and actually transacted some 4.4 billion won until 2013, but the funding ended after Kang stepped down as KDB chief, according to prosecutors.

The prosecution sought a warrant to formally arrest him in late September, but the request was declined by a judge who said Kang's major crime allegations are still disputable.

Prosecutors are expected to file for the warrant again after the interrogation. 

Kang's alleged irregularities emerged after prosecutors launched a full-fledged investigation into the shipyard earlier this year.

Daewoo Shipbuilding is one of the country's big three shipbuilders that have been implementing drastic self-rescue programs, including asset sales and workforce reduction, in order to tide over a protracted slump and cut costs.

Earlier this year, the shipyard said it had much larger losses in 2013 and 2014 than earlier reported, citing accounting mishaps.

The Board of Audit and Inspection, the country's state audit agency, has said the shipyard is suspected of rigging its books to hide up to 1.5 trillion won in losses during the period.

Its former chief Nam as well as his successor Ko Jae-ho are currently on trial over a string of corruption allegations. (Yonhap)