A South Korean court has approved an arrest warrant for a long-time friend of President Park Geun-hye.
Choi Soon-sil is suspected of using her friendship with the president to interfere in state affairs and to solicit business donations for a non-profit fund she controlled.
The allegations have prompted growing calls for President Park to resign.
Her office has announced she will make a public statement on the situation on Friday.
Ms Choi has been in custody since Monday, being questioned by prosecutors over a string of allegations.