Park was indicted in January 2018 on charges of accepting 3.5 billion won from three NIS chiefs from May 2013 to September 2016 in collusion with her secretaries and sentenced by the Seoul Central District Court in July of the same year to six years in jail and a forfeit of 3.3 billion won. At that time, the district court acquitted Park of bribery and applied a charge of loss of state funds in determining her sentence.

As for the partial acquittal, the Seoul High Court said on July 25 that the NIS chiefs accused of handing their "special activity funds" to Park cannot be regarded as accounting officials stipulated by the laws on the loss of state funds.

But the Supreme Court said the lower courts' decisions to acquit Park of state fund loss and bribery charges were wrong and that she should be seen as guilty of such charges.

The top court stressed the three former NIS chiefs accused of paying NIS money to Park should be regarded as accounting officials under the current law and that the lower courts wrongly interpreted the relevant legal principles.

With the retrial order, the length of Park's prison term is expected to increase.

The Supreme Court also sent the cases of three former spy chiefs -- Nam Jae-joon, Lee Byung-kee and Lee Byong-ho -- back to the Seoul High Court, saying they should all be given heavier sentences. About one year ago, the appellate court reduced Nam's jail term to two years, while Lee Byung-kee and Lee Byong-ho received imprisonments of two and a half years each.

The court said Park and Lee Byong-ho, in particular, should be additionally punished on bribery and state fund loss charges for the delivery of 200 million won in September 2016.

Park was not present at Thursday's top court trial, as she has been boycotting all her trials.

Park is now serving a total of 32 years in prison for bribery, abuse of power, election law violations and other charges.

Following her ouster from the presidency in 2017, Park was convicted of power abuse and various corruption charges.

On Aug. 29, the Supreme Court ordered a retrial of the corruption case in which Park was sentenced to 25 years in prison by an appeals court. The top court said some of the bribery charges should be dealt with separately, which may lead to heavier punishment.

Separately, the Seoul High Court sentenced Park to a two-year prison term last November on charges of illegally interfering in the then-ruling party's candidate nominations ahead of the general elections in April 2016. The jail term was confirmed after both Park and prosecutors didn't appeal to the Supreme Court.

In April this year, Park filed for the suspension of her sentence, saying her health has badly deteriorated due to the lengthy detention. She was detained on March 31, 2017. But Seoul prosecutors dismissed her petition after examining her health and other conditions. In September, she underwent shoulder surgery at a hospital in Seoul. (Yonhap)