Updated

Usama bin Laden's son is reportedly emerging as a key player in the Al Qaeda (search) terror network.

U.S., European and Arab officials tell The Washington Post that Saad bin Laden (search), who is believed to be 24, is part of a small group running Al Qaeda from Iran.

According to the newspaper, intelligence sources say Saad bin Laden and other Al Qaeda operatives were in touch with a terror cell in Riyadh, Saudi Arabia, just before the May 12 homicide attack there that killed 35 people, including eight Americans.

The officials say the younger bin Laden is guarded by an elite force of Iranian radicals loyal to the nation's clerics.

The Post says U.S. officials have warned the Iranian president that harboring Al Qaeda members will have serious consequences. Iran was one of the nations that President Bush had described as being part of an "axis of evil."