The writer's brother said that Abdel-Samad went missing Sunday afternoon, after he informed his guards a black car had followed him. The 41-year-old author of Egyptian origin has often written critically of Islamists, and became internationally well-known after the 2009 publication of his "My Farewell from Heaven" (Mein Abschied vom Himmel). Following the book's printing in Egypt, an Islamist group made death threats against the writer.

"Hamed got kidnapped on Sunday at 4 p.m. He was walking in the Al Ashar Park area," Abel-Samad's brother Mahmoud told DW.

"It is a very difficult time for the family," he said, adding he believed his brother was kidnapped by "radical Islamists."

Mohammed Hashem, the head of Merit Publishing House, which announced that Abdel-Samad had prepared a new book on religious fascism, said he hoped Abel-Samad would come "back to continue his role as a free writer who defends his ideas and principles."

"It is inconceivable that we continue to live under the threat of terrorists and extremists who believe it is permissible to kill writers and intellectuals," Hashem added.

Abdel-Samad received death threats in June and religionists described him as an infidel, after he gave a speech in Cairo in which he criticized radical Islam and Egypt's Muslim Brotherhood.

On Monday, Martin Schäfer, a spokesman for the German Foreign Ministry, said that a crisis team was working on the case, though he would not confirm whether the writer had been kidnapped.

Schäfer said that, prior to his disappearance, Abdel-Samad had brought up concerns about his safety to the German embassy in Cairo. Germany's federal government has made contact with Egyptian authorities, seeking a swift answer to the question of Abdel-Hamad's whereabouts.

mkg,dr/ph (AFP, dpa)