A former aide to South Korea’s President Park Geun-hye has been detained by prosecutors, say officials.
Officials say Ahn Jong-beom is the second aide to be detained in a scandal which is threatening the president’s position.
He and Ms Park’s long-time friend and mentor Choi Soon-sil are suspected of using their presidential connections to persuade corporations to donate funds to foundations they were involved with.
Ms Choi was detained on Monday and is still being held.
Report says Mr Ahn had told reporters on Wednesday that he would take responsibility for his actions.
Prosecutors said he has been placed under emergency detention to prevent the possibility of him tampering with evidence. They have 48 hours to formally request an arrest warrant in court.
On Wednesday South Korean prosecutors requested an arrest warrant for Ms Choi.
According to a court spokesman, Seoul Central District Court is due to review the request on Thursday.
Several banks have also been raided in connection with the controversy, which has prompted widespread anger.
At the heart of the scandal is the influence that Choi Soon-sil, the daughter of a shadowy religious cult leader, may have had on President Park.
The allegation is that Ms Choi was involved in high-level decision making and handled classified documents without security clearance. She is also accused of embezzlement. But Ms Choi has denied the allegations.
The true extent of Ms Choi’s influence is unclear. The women have been friends since the 1970s when Ms Choi’s father, Choi Tae-min, befriended Ms Park’s family. He eventually became Ms Park’s mentor.
She is embroiled in a battle for her political life as a result of the scandal. She has apologised to the public for causing national concern.
Ms Park responded to the crisis on Wednesday by reshuffling her government, appointing a new finance minister and prime minister, which is a largely symbolic role in South Korea.
Surveys suggest her approval rating is about 10%, with about half of respondents saying she should resign or face impeachment.