RIYADH -- Osama bin Laden's eldest son, Saad, has taken over the command of the Al-Qaeda terror network blamed by Washington for the September 11 attacks, the Saudi pan-Arab daily *** Asharq al-Awsat *** reported Monday.

Saad bin Laden has been in charge of the organization "since the U.S. offensive against Al-Qaeda bases in Afghanistan," which began in October, and Al-Qaeda's pullout from its main hideouts in the country, the paper quoted "informed sources" as saying in a London-datelined dispatch.

This disclosure "substantiates the theory that Bin Laden was killed or seriously wounded" in the U.S.-led military campaign, the paper said.

Bin Laden's second son, 20-year-old Mohammad, had previously been expected to succeed the suspected terror mastermind in case of his death or incapacitation, *** Asharq al-Awsat *** said, adding that Saad was "unknown" outside Al-Qaeda.

Bin Laden has some 20 sons from various wives, the paper said.

Speculation about Bin Laden's fate has abounded since the U.S.-led bombardment of Al-Qaeda hideouts began.

Dale Watson, head of the FBI's anti-terrorist unit, said in mid-July that he believed Bin Laden was probably dead but added he had no evidence to support his contention.