Small rallies were held after Friday prayers in several Islamic nations. Al-Qaeda and Islamic militants vowed to avenge the killing of Osama bin Laden by US commandos, declaring him a \"martyr\" and calling on Muslims to rise up against the United States. But US President Barack Obama swept aside the militants\' defiant reaction, decorating the team that killed their inspirational leader and pledging the United States would crush Al-Qaeda.
\"We have cut off their head and we will ultimately defeat them,\" Obama said after meeting in private with the special forces personnel that raided bin Laden\'s hideout in Pakistan on Monday and shot dead the Al-Qaeda leader.
Confirming bin Laden\'s death for the first time, the terror network denounced his slaying urging Pakistani Muslims \"to cleanse their country from the filth of the Americans who spread corruption in it.\"
The Afghanistan Taliban also joined the chorus of condemnation -- as small rallies were held after Friday prayers in several Islamic nations -- saying the loss of the architect of the September 11, 2001 attacks would only serve to strengthen its resolve in the fight against \"foreign invaders.\"
\"We call upon our Muslim people in Pakistan, on whose land Sheikh Osama was killed, to rise up and revolt to cleanse this shame,\" Al-Qaeda said in a statement released by the SITE monitoring group.
The Islamist group proclaimed its Saudi-born founder a \"martyr,\" adding he had \"terrified all the nations of disbelief.\" It vowed the jihadist network would survive, but did not name anyone to take over as its leader.
The White House said it was on alert for security threats as Al-Qaeda also vowed to release an audio tape made by bin Laden just a week before he was shot.
The Obama administration, embroiled in a decade-long war in Afghanistan, is keenly aware of the dangers facing US interests and nationals abroad.

US forces ousted the Taliban from power in 2001 following the 9/11 attacks in retaliation for harboring bin Laden on Afghan soil.
And the Afghanistan Taliban said bin Laden\'s death \"will give a new impetus to the current jihad against the invaders in this critical phase of jihad,\" an email statement released by spokesman Tariq Ghazniwal said.
The leader of the Palestinian Islamist movement Hamas, Khaled Meshaal, also condemned what he called \"extrajudicial executions.\"
\"While we disapprove of the methods of Al-Qaeda, particularly actions directed against innocent civilians, we are opposed to the United States or any other party having recourse to extrajudicial executions,\" he said in a statement to AFP.
Obama Friday met the elite commando team which carried out the risky helicopter-borne raid on the fortified compound in the Pakistani town of Abbottabad where bin Laden had been hiding.
He said he had told them \"job well done\" as he handed out Presidential Unit Citations, the highest unit award he has the power to grant, behind closed doors at an army base at Fort Campbell, Kentucky.
The meeting comes a day after Obama laid a wreath at Ground Zero, the site where the felled World Trade Center once stood, in a somber moment aimed at bringing closure to Americans still haunted by the September 11 attacks.
The White House has been eager to avoid any triumphalism over the elimination of the world\'s most wanted man, blamed for the deaths of almost 3,000 people in the attacks, in a bid to avoid whipping up Muslim anger.
But on the traditional day of prayers, hundreds of Islamists rallied in Pakistan, Egypt, Turkey and Britain calling for revenge.

In Abbottabad, just 50 kilometers (30 miles) from the capital Islamabad, where bin Laden was finally tracked down after a years-long manhunt, police marshaled a rally of about 1,000 men.
Setting fire to tires and blocking a main road, the protesters yelled: \"Down, down USA!\" and \"Terrorist, terrorist, USA terrorist.\"
Hundreds took to the streets in the insurgency-riven Pakistani city of Quetta calling for holy war against America, while Islamists also rallied in the Egyptian capital of Cairo.
About 200 people, including a small group of veiled women, also gathered outside an Istanbul mosque carrying pictures of bin Laden. And in London, over 100 Islamic extremists rallied outside the US embassy.
\"It is only a matter of time before another atrocity -- the West is the enemy,\" protestor Abu Muaz, 28, from east London, said.
Intelligence seized during Monday\'s operation showed that despite his isolation bin Laden had remained closely involved in Al-Qaeda operations up until his death.
The network had even been mulling strikes on US trains on the 10th anniversary of the 9/11 attacks, US officials said.
It is not yet clear how much bin Laden\'s death is likely to affect Al-Qaeda\'s operational capabilities and its ability to carry out attacks.
Questions have also been raised about how bin Laden managed to hide out for so long in Pakistan, in a town which is home to a top military academy and many retired generals.
Former Pakistani president Pervez Musharraf blamed the \"incompetence\" of his country\'s intelligence services, saying he was upset bin Laden had been hiding in Pakistan when he was still in office.
In another sign of potential lapses by the Pakistani intelligence services, the Washington Post reported the CIA had maintained a safe house in Abbottabad for several months to spy on bin Laden\'s compound.
The close-up spying operation allowed them to draw up a \"pattern of life\" for the occupants inside, the paper said.
The United States had intercepted a phone call to bin Laden\'s main courier, who told his friend calling that \"I\'m back with the people I was with before,\" the Post reported.
The call gave intelligence officials the number of the courier\'s cellphone. Using \"a vast number of human and technical sources,\" the newspaper reported, they tracked the courier to the compound.
US officials learned that anyone leaving the compound would drive 90 minutes away before making calls, so as to avoid electronic surveillance, the Post reported.
The Obama administration has been forced to defend the raid\'s legality after acknowledging bin Laden was unarmed when he was shot dead.
But new details have been released of the operation after conflicting accounts from the White House. The SEALs also found an AK-47 and a pistol in his room, a US official told AFP Thursday.
\"He had weapons in his room, more than one,\" said the official, who spoke on condition of anonymity. \"He was not compliant. He did not surrender.\"