The leader of the Unification Church religious empire, Han Hak-ja, was jailed after a South Korean court on Tuesday issued a warrant to detain her in relation to graft allegations against the wife of ousted President Yoon Suk Yeol, prosecutors said.
"The Seoul Central District Court issued the warrant on the ground she poses the risk of tampering with evidence," the prosecution said in a statement.
Han, 82, was questioned last week over her alleged role in bribing former first lady Kim Keon Hee and a prominent lawmaker. Prosecutors sought her arrest a day later.
After the warrant was issued, Han was remanded in custody at the Seoul Detention Center.
The Unification Church was founded in 1954 by Han's late husband Moon Sun-myung and has long been the subject of controversy.
Moon claimed to be the second coming of Jesus Christ, while the church has a cultlike culture and its followers are derisively referred to as "Moonies."
It has a vast reach, with businesses ranging from media and tourism to food distribution.
"We humbly accept the court's decision," the church said in a statement on the arrest.
"We will sincerely cooperate with the ongoing investigation and trial procedures to establish the truth, and we will do our utmost to take this as an opportunity to restore trust in our church," it added.
"We deeply apologize for causing concern."
Han assumed leadership of the organization after Moon's death in 2012.
She is suspected of ordering the delivery of luxury gifts, including a designer handbag and diamond necklace, to Kim in 2022 to curry favor with her husband, Yoon, who became president that year.
The former first lady has been arrested and indicted on charges of bribery and stock market manipulation. Her husband is also in custody and is standing trial over his declaration of martial law in December.
Han also faces allegations of bribing a prominent lawmaker with 100 million won ($72,000).
As she was wheeled out of the prosecutors' office after more than nine hours of questioning last week, Han denied wrongdoing.
"Why would I have done that?" she said when asked about the allegations.
Before her Tuesday arrest, the church denounced prosecutors' request for a warrant as "unjust persecution of a global religious leader."
"We firmly denounce the fact that, instead of humanitarian consideration and rational judgment, excessive and coercive measures have been taken against our leader," it said in a statement last week.
The church, which is formally called the Family Federation for World Peace and Unification and claims to have 10 million followers worldwide, is best known for its mass weddings, where thousands of couples from across the globe are married in stadium-sized ceremonies.
It has also faced criticism for its fundraising and other issues, most recently over a political scandal in Japan in the wake of former Prime Minister Shinzo Abe's assassination.
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