Senior figures in the Britain, France and the US warned on Tuesday that there are real risks that al-Qaeda and its affiliates could try to carry out a revenge attack following the assassination of Osama bin Laden, warning citizens in their countries to be vigilant.
Although terrorist threat levels were not raised in any of these countries, David Cameron, Britain’s prime minister, sounded a cautious note.
“Clearly there is a risk that al-Qaeda and its affiliates in places like Yemen and the Maghreb will want to demonstrate they are able to operate effectively,” Mr Cameron told the House of commons in a statement on bin Laden’s death. “And, of course, there is always the risk of a radicalised individual acting alone, a so-called lone-wolf attack.”
Mr Cameron added: “We must be more vigilant than ever – and we must maintain that vigilance for some time to come.”
In France, François Fillon, prime minister, said on Tuesday that the government will bolster security at home and around its assets abroad to guard against reprisals. “We have decided to increase vigilance on our territory," he said during a weekly question session in parliament.
"We have also asked our embassies to increase their security as well as for companies that operate in the world's most dangerous regions."
Eric Holder, US attorney-general, added further warnings as he urged law enforcement agencies not to become complacent after his death.
“Just yesterday I ordered the [Justice] department's prosecutors and law enforcement agencies to be mindful that bin Laden's death could result in retaliatory acts in the United States or against our interests overseas," Mr Holder told a Senate hearing.
Al-Qaeda's north African wing, AQIM, has become a threat for French companies in Africa's Sahel region after five employees of Areva, the energy group, were taken hostage last September.
In Britain and the US, there has been no decision to raise the government assessment of the threat to citizens. In both cases, this is because there is no information of a specific new threat which is nearing implementation.
Mr Cameron said: “The terrorist threat level in the UK is already at “severe” – which is as high as it can go without intelligence of a specific threat. We will keep that threat level under review – working closely with the intelligence agencies and the police.”
The prime minister added that the government had updated its formal advice for British citizens travelling abroad. He said UK nationals were encouraged “to monitor the media carefully for local reactions, remain vigilant, exercise caution in public places and avoid demonstrations.”