SK Group‘s vice chairman was called back for questioning by prosecutors Wednesday on suspicions he embezzled nearly 100 billion won ($88.7 million) of the group’s funds in collusion with his elder brother.

Chey Jae-won reappeared at the central prosecutors‘ office in southern Seoul at around 10 a.m., for his second interrogation over the embezzlement charges. It came less than a week after he underwent 16 hours of intensive interrogation on Friday.

“I came here to sincerely answer questions (that had not been sufficiently answered),” Chey told reporters before entering the office.

Chey Tae-won, the elder brother and group chairman, will be summoned later this week, prosecutors said Tuesday.

The brothers, sons of SK founder Chey Jong-hyon, face allegations that they misappropriated the funds, which were part of a total of 280 billion won set aside by 18 SK affiliates for investment purposes.

The embezzled funds were reportedly used to make up for as much as 300 billion won in losses incurred as a result of the 51-year-old chairman’s unsuccessful stock futures investments.

The younger brother is suspected of having led the embezzlement scheme.

The vice chairman reportedly refuted the embezzlement accusations during the interrogation last week, but prosecutors are believed to have secured evidence pointing to the brothers‘ illegal use of the affiliates’ funds.

SK Group controls dozens of affiliates in various industrial segments, including top oil refiner SK Innovation and No. 1 wireless telephone service provider SK Telecom. (Yonhap News)