The vice-president of the International Olympic Committee (IOC), South Korea's Kim Un-Yong, has been arrested on corruption charges.
The move followed a 15 hour interrogation of the 72-year-old sports administrator, who was suspended by the IOC last week.
After prosecutors in Seoul grilled Kim he was allowed to return to a hospital today. He had been in an intensive care unit since he collapsed two weeks ago just as prosecutors were planning to arrest him.
But later it was decided to jail him after prosecutors were told he had no serious health problems.
Kim, a long-time IOC member and one of South Korea's most powerful sports leaders, played a key role in helping South Korea host the 1988 Olympics.
He is suspected of embezzling funds donated by businessmen to taekwondo organisations. He is also accused of receiving money from a South Korean sportswear company after helping it become an official sponsor for the Korea Olympic Committee.
An IOC statement last Friday said the executive board had decided unanimously to deprive Kim of "all the rights, prerogatives and functions deriving from his IOC membership" until the investigation and a report from its own ethics commission had been completed.
A statement from Kim's New York office said the suspension was "contrary to the principle of presumed innocence which prevails in civilised countries throughout the world".
"The IOC should indeed await the results from inquiries in Korea regarding Dr Kim. But this action against him is harsh, unjust and reflects more unfavourably upon its leadership than on the subject of its wrongful action," it said.