A Rwandan court has denied bail to Paul Rusesabagina, who was portrayed as a hero in a Hollywood movie about the 1994 genocide.
Mr Rusesabagina, who was living in exile until he arrived in Rwanda under mysterious circumstances at the end of last month, is facing charges of terrorism among other crimes.
In court, the 66-year-old spoke for himself and appealed against the bail denial decision, an independent journalist told the BBC.
The judge said that there were concerns that, if released, Mr Rusesabagina "would disrupt the ongoing investigation".
The court decision means that he will now be moved from police custody to prison.
He is charged with crimes relating to the FLN rebel group's deadly attacks in south-western Rwanda in 2018 and 2019.
Mr Rusesabagina is a leader of the opposition MRCD group, and the FLN is thought to be the group's armed wing.
He became well known after the 2004 film Hotel Rwanda depicted his efforts a decade earlier during the genocide to save hundreds of Tutsis at a hotel where he was a manager.
Rwandan genocide survivors' group Ibuka has in the past said that he exaggerated his own role in helping hotel refugees escape the 100-day slaughter.