FILE PHOTO: Author Tariq Ramadan talks with a journalist after a conference at the Er-Rahma mosque in Nantes, France, April 25, 2010. REUTERS/Stephane Mahe/File Photo

PARIS (Reuters) - A French judge decided on Tuesday to keep Swiss Islamic scholar Tariq Ramadan in custody pending a possible trial for allegations of rape, a source with the prosecutor’s office said.

Ramadan, who denies the allegations, was notified on Friday that he would be the target of a full investigation and had been in detention since.

After a debate between his lawyers, prosecutors and magistrates, judges decided not to release him, taking the inquiry a step further.

Under French law, investigating magistrates can still decide not to hold a trial, depending on the evidence. Temporary custody is usually reserved for cases where the accused might be a flight risk.