SEOUL (Reuters) - South Korean special prosecutors team have filed fresh charges including bribery against a close friend of impeached President Park Geun-hye, the central figure in a political scandal that has engulfed the country, the team said on Monday.

Choi Soon-sil, the woman at the centre of the South Korean political scandal and long-time friend of President Park Geun-hye, appears for her first trial at the Seoul Central District Court on January 5, 2017 in Seoul, South Korea. REUTERS/Chung Sung-Jun/Pool

Choi Soon-sil, in jail since late October and on trial since last month, already faces charges of abuse of power and attempted fraud. On Monday, Lee Kyu-chul, spokesman for the special prosecution team, said it had filed the additional charges.

He declined to provide further details during a regular briefing. Choi’s lawyers were not immediately available for comment.Choi, 60, who has known Park for four decades, is accused of colluding with Park to pressure big businesses, including Samsung Group, to contribute to non-profit foundations backing the president’s initiatives.

Choi has denied any wrongdoing.

Also on Monday, two senior executives of Samsung Group [SAGR.UL] were questioned as part of the corruption probe.

South Korean prosecutors are trying to ascertain whether Samsung, the country’s biggest conglomerate, sought favors from Choi and Park in return for funding some of their initiatives.

No Samsung officials have been accused of wrongdoing.

As part of their investigation, prosecutors are also looking into Samsung’s sponsorship of the equestrian riding career of Choi’s daughter, Chung Yoo-ra, 20, who was arrested in Denmark after being sought by South Korean authorities.

Chung has been accused of criminal interference related to her academic record and other unspecified charges.

Upon their arrival at the special prosecutor’s office on Monday, Choi Gee-sung and Chang Choong-ki, executives from Samsung’s future strategy office, declined to comment.

The two were being questioned as witnesses but their status can change, the special prosecutor’s office has said.

Park has denied any wrongdoing but admitted carelessness in her dealings with Choi, who is accused of wielding inappropriate influence over state affairs.

The Constitutional Court will decide whether or not to uphold Park’s impeachment, a process that could take months.