Police in Cairo are investigating the disappearance of an Egyptian-born German author and critic of Islam, security sources said on Tuesday, months after a cleric declared him an infidel and called for his death.

Hamed Abdel-Samad, author of "The Downfall of the Islamic World: A Prognosis", went missing in recent days, according to a missing person's report filed by his brother, police sources said. An Egyptian newspaper report said he had been abducted. (Reuters)