True identity of al-Masri still an enigma

"His real name is Yussef al-Dardiri, he is around 38 years old and he comes from Upper Egypt," Montasser al-Zayat, a lawyer and former member of the Islamist group Gamaa Islamiya, told AFP.

But Egyptian security sources insist they have not heard of the name.

"The Egyptian security services have not heard of any Egyptian by this name, but since his name has been released, we are researching and investigating the matter," a security source said.

Diaa Rashwan, an expert on political Islam at Cairo's Al-Ahram Center for Strategic Studies, said he too had not come across the name. "There is no trace of such a name in the Egyptian radical Islamic files," he said.

The US military on Thursday released pictures of the Egyptian who it said was the successor of Zarqawi, who was killed in a US air strike north of Baghdad on June 7.

Coalition forces spokesman Major General William Caldwell said the new leader, Abu Ayyub al-Masri (meaning 'the Egyptian' in Arabic), also known as Sheikh Abu Hamza al-Muhajer (meaning 'the immigrant'), was believed to be operating out of Baghdad.

Al-Qaeda, which has not disclosed the new leader's nationality, "on its website has named him as Abu Hamza al-Muhajer, but we believe that he is one and the same", Caldwell told reporters.

According to Zayat, who says he does not know Masri personally, Zarqawi's successor lived in the central Cairo area of Zawyia Hamra before going to Afghanistan in the late 1980s or early 90s, and then on to Iraq via Iran.

Zayat is the main lawyer for the Gamaa Islamiya and Islamic Jihad, two Islamic militant groups which were behind a wave of violent attacks that killed 1,300 people in Egypt during the 1990s.

A government crackdown left the two groups' members killed, behind bars or fleeing the country, while others renounced the use of violence in their campaign for an Islamic state.