GENEVA (REUTERS) - A Swiss woman has filed a criminal complaint in Geneva for rape against the Islamic scholar Tariq Ramadan - already being held in custody in France on similar allegations - her lawyer said on Friday (April 13).

The allegation by the unnamed Swiss woman, a convert to Islam, relates to an alleged incident in Geneva in October 2008, the daily Tribune de Geneve said, citing a 13-page document. The woman was about 40 at the time.

"At this stage of the procedure, I can confirm that we have filed a criminal complaint," her lawyer Romain Jordan told Swiss Television TSR on Friday night.

"The complaint puts forward facts that may amount to rape with aggravated circumstances." He declined to give further details.

Yael Hayat, one of Ramadan's lawyers in Geneva, declined to comment on television, saying she was unaware of the case filed with the Geneva prosecutor. The prosecutor's spokesman did not immediately respond to a query.

In France last month, a 45-year-old woman filed a new rape case against the Swiss academic, the third against the Islamic studies professor, judicial sources said.

Ramadan, 55, was ordered in February to remain in custody in France and was notified that he was the target of a full investigation into rape allegations, which he denied.

Married with four children, he is a grandson of Hasan al-Banna, an Islamist thinker and activist who founded the Muslim Brotherhood in Egypt. He enjoys a substantial following among young Muslims and has challenged French restrictions on wearing veils.

Ramadan took a leave of absence from his professorship at Britain's Oxford University last November after the first two women filed complaints against him in France alleging rape.