SEOUL - Choi Soon-sil, a decades-long friend of ousted South Korean President Park Geun-hye, was sentenced to 20 years in jail on the conviction for multiple corruption charges, heralding a heavy sentence on Park who was identified as an accomplice to Choi.

The Seoul Central District Court sentenced Choi to 20 years behind bars and fined her 18 billion won ($16.6 million) for multiple convictions including abuse of power, extortion and bribery.

Prosecutors originally demanded 25 years in prison for Choi, with a fine of 118.5 billion won ($109 million) and a forfeit of 7.79 billion won ($7.18 million).

The court ruling said Choi, who was at the center of the influence peddling scandal that led to Park's impeachment in March last year, abused the presidential power and forced large conglomerates to donate tens of millions of dollars to two nonprofit foundations controlled by Choi.

She was also convicted of receiving 7.29 billion won ($6.7 million) in bribes from Samsung Electronics Vice Chairman Lee Jae-yong, an heir apparent to Samsung Group, the country's biggest family-controlled conglomerate.

Independent counsel Park Young-soo and state prosecutors claimed that Choi received, or promised to receive, 43.3 billion won ($39.9 million) from the Samsung heir who was released from prison after the appeals court's ruling last week.

Lee got a jail term of two and a half years with a stay of execution for four years in the appellate court's trial. The Samsung heir was set free after having been put under custody for almost a year.

The longtime confidante of the impeached president was taken into custody in November 2016, and was indicted in the same month for 18 corruption counts. She was accused of intervening in state affairs from the shadows even though she had no official post in the Park government.

The verdict on Choi heralded a heavy punishment on the ousted president as the court ruled that Choi was complicit with Park in abusing the presidential power and extorting a huge money from large conglomerates.

The sentencing trial for Park was forecast to be held in late March. Park has refused to appear in court hearings in protest at the decision to extend the presentencing detention of Park for as long as six months in October last year.

Meanwhile, An Chong-bum, former senior secretary for Park, was sentenced to six years in jail and fined 100 million won ($92,225). Prosecutors originally requested a six-year imprisonment for An.

The court verdict said An was complicit with Choi and Park in coercing tens of conglomerates to make donations to the Choi-controlled foundations.

Lotte Group Chairman Shin Dong-bin got a jail term of two and a half years for bribery, forfeiting 7 billion won ($6.5 million). Prosecutors demanded four years in jail.

Shin was immediately put under custody in the courtroom. The court ruled that the Lotte chairman offered 7 billion won in bribe to one of the Choi-controlled foundations in return for business favors.