Al Qaeda leader Osama bin Laden has appeared in a videotape with a top aide on Al Jazeera Arabic television to mark the second anniversary of the September 11th attacks on the United States.
Bin Laden and Ayman al-Zawahri, his right-hand man, were shown in a rare tape, descending a rocky mountainside as they steadied themselves with walking sticks, automatic rifles slung over their shoulders.
The tape had an audio message said to be from Saudi-born bin Laden in which he praised the 19 suicide hijackers who crashed planes into New York's World Trade Center, the Pentagon in Washington and Pennsylvania two years ago today.
"Whoever wants to be taught about loyalty and honesty should have known them (the attackers)... They were the most honest and the bravest," he said.
Bin Laden said the panic caused by the attacks made "people wake up from their slumber and rise for jihad (holy war)."
The CIA and analysts around the world immediately began poring over the tapes to gauge their authenticity and scour them for clues of when and where they might have been made. Al Jazeera said the video was probably filmed in April or May.
Messages from al Qaeda leaders are often seen as a signal to supporters to mount attacks. FBI and US Homeland Security officials warned last week of the threat of more al Qaeda attacks on the United States.
Zawahri said US efforts to crush al Qaeda had failed and the network had instead grown in the past two years. He promised more attacks to "punish" the United States.
"This is the second anniversary of the New York and Washington invasions which defied America and its crusade from whose wounds it is still staggering in Afghanistan and Iraq.
"We tell you (America) that what you have seen so far are only the first skirmishes and the beginning of the clash. The real battle, however, has not started yet."
"We are not advocates of killing and destruction, but with the help of God, we will cut the arms of anyone that touches us or carry any aggression against us, so prepare yourself for punishment for your crimes," Zawahri said.
Zawahri added: "To our struggling brothers in Iraq: we greet you and we pray to God to be on your side in fighting the crusaders," Ayman al-Zawahri, or someone sounding very much like him, said on the tape.
"God is with you and the entire nation supports you. Rely on God and devour the Americans just as lions do with their prey, and bury them in the graveyard of Iraq."
President Bush said last night al Qaeda "still plots against our people" and would be defeated.