The Egyptian who guards Osama bin Laden has taken over as Al- Qaeda's military commander, a terror expert said on Monday.

Saif al-Adel, who is believed to have turned 40 last month, has a $25 million price on his head. The United States had indicted him over the 1998 bombings of the US embassies in Kenya and Tanzania.

Al-Qaeda turned to Adel after Khalid Sheikh Mohammed's arrest in Pakistan removed the military commander whose careful years of planning resulted in the 9/11 attacks, said Rohan Gunaratna, author of Inside Al Qaeda: Global Network of Terror.

"They chose him because he is their most competent man and he fits into the typical Al-Qaeda, Islamic jihad mindset," said Gunaratna, now based in Singapore.

Adel has shown ruthless efficiency in his role as chief of Al- Qaeda's security and above all in protecting Laden, he said.

Adel may bring a different style to future attacks.

"They will become much more secretive, much more discreet, they will learn from mistakes of the past," said Gunaratna.

Adel's photograph on the Federal Bureau of Investigation's most- wanted list shows a clean-shaven, narrow-faced young man. He is believed, like Laden, to be hiding along the porous Pakistan-Afghanistan border.

His responsibilities have involved registration and screening of new members, developing communications systems and above all protecting his chief.

"He is an extraordinarily bright man," said Gunaratna. "He has to be given credit for the survival of Osama bin Laden and this demonstrates that he can match the penetration capabilities of those who want to capture bin Laden."

He has yet to make his mark as the new commander.

"The current spate of operations were planned and prepared by Khalid Sheikh Mohammed and by Tawfiq bin Attash," he said of last week's strikes in Riyadh, Saudi Arabia, and Casablanca, Morocco.

"These had been in the planning stage for a long time."

Attash, a one-legged Saudi of Yemeni origin believed to have been a bodyguard to Laden, was arrested in Pakistan this month.