Samsung Group Chief Jay Y. Lee was arrested on Friday, Feb. 17. After spending the night in a small cell, he was grilled by South Korean authorities on Saturday, Feb. 18.

The 48-year-old Lee has a net worth of $6.2 billion. He heads the technology giant Samsung, one of the world's biggest manufacturers of smartphones, flat-screen televisions, memory chips, and other devices.

Lee was handcuffed and tied with white rope when he arrived at the special prosecutor's office at about 2:20 pm (0520 GMT). He wore a dark suit, white shirt, and no tie. He was escorted by officials from a justice ministry van, Reuters reports.

The Samsung chief was questioned by South Korea's special prosecutor for more than 15 hours as part of the investigation. Lee has been accused of involving into a graft scandal that has led to impeach President Park Geun-Hye.

The special prosecutor's office plans to widen the charges and accuses Lee of bribing a close friend of the president to gain government favors related to leadership succession, SBS reports. Aside from bribery, the prosecutor also indicts him on charges which include embezzlement, hiding assets overseas, and perjury.

South Korea's special prosecutor has been focussing on Samsung Group Chief's relationship with Park, which has been linked to the accusation of Lee's capacity as Samsung chief of pledging 43 billion won ($48.9 million) to a business and organization. While Lee has been questioned by officials on Monday, he denied all the allegations of bribery.

"I will once again tell the truth to the special prosecution," Lee told the reporters. According to the special prosecution team, investigators questioned two other Samsung executives who are considered suspects. One of those two is Samsung Electronics president Park Sang-jin. He did not respond to the reporters when he arrived at the special prosecution team's office, according to SMH.

S. Korea parliament impeached Geun-Hye in December. She has been stripped of her power in the meantime.