The US government warned on Monday that Osama bin Laden's death at the hands of US forces could trigger retaliatory attacks in the United States and Europe, and against Western targets around the world.
"The Intelligence Community (IC) assesses the death of al Qaeda leader Osama bin Laden could result in retaliatory attacks in the Homeland and against US and Western interests overseas," said the US Department of Homeland Security.
The department, in a bulletin for law enforcement officials said attacks could originate among core al Qaeda members in Pakistan's remote tribal areas, among the group's overseas affiliates, or individuals who are not formal members but who identify with the extremist network.
"Overseas, the strongest reaction is expected to be in South Asia but will likely occur to differing degrees worldwide, including Europe," warned the department, which was created after the September 11, 2001 attacks.
"Other high-risk regions include those where al Qaeda's affiliates and allies have operational strongholds, including the Middle East, Africa, and Southeast Asia," it said in the message.
"The IC lacks current insight into al Qaeda's selection of Homeland targets, but as seen in previous al Qaeda plotting symbolic, economic, and transportation targets could be at risk," the department warned.
"Small-arms attacks against soft targets, which could be perceived as more achievable than other types of attacks, cannot be ruled out," it said, noting it had "no indications of advanced al Qaeda core plotting efforts" on US soil.
But Bin Laden's death may lead al Qaeda operatives to "accelerate" planning for attacks in the US and "may provide justification for radicalised individuals in the US to rapidly mobilize for attacks here."